diff --git a/app/split-netcdf-python/README.md b/app/split-netcdf-python/README.md
deleted file mode 100644
index e0939ae2..00000000
--- a/app/split-netcdf-python/README.md
+++ /dev/null
@@ -1,11 +0,0 @@
-# split-netcdf
-
-Split NetCDF files by variable
-
-Some sample input parameters for rose-app.conf
-inputDir=/work/c2b/canopy/split-netcdf
-outputDir=$TMPDIR/tmp
-date=19210101T0000Z
-component=river_month_inst
-
-rose app-run
diff --git a/app/split-netcdf-python/bin/split-netcdf b/app/split-netcdf-python/bin/split-netcdf
deleted file mode 100755
index 7723a017..00000000
--- a/app/split-netcdf-python/bin/split-netcdf
+++ /dev/null
@@ -1,94 +0,0 @@
-#!/bin/python
-
-# Split NetCDF files by variable
-#
-# Can be tiled or not. Component is optional, defaults to all.
-#
-# Input format:  date.component(.tileX).nc
-# Output format: date.component.var(.tileX).nc
-
-import os
-import glob
-import subprocess
-import cdo
-import sys
-from pathlib import Path
-
-#Set variables
-inputDir = os.environ['inputDir']
-outputDir = os.environ['outputDir']
-date = os.environ['date']
-component = os.environ['component']
-use_subdirs = os.environ['use_subdirs'] 
-
-print("Arguments:")
-print("    input dir: "+inputDir)
-print("    output dir: "+outputDir)
-print("    date: "+date)
-print("    component: "+component)
-print("    use subdirs: "+use_subdirs)
-print("Utilities:")
-type(cdo)
-
-#Verify input directory exists and is a directory
-if inputDir == "":
-    print("Error: Input directory "+ inputDir + " does not exists or isnt a directory")
-    sys.exit(1)
-
-#Verify output directory exists and is a directory
-if outputDir == "":
-    print("Error: Output directory" + outputDir + " does not exist or isn't a directory")
-    sys.exit(1)
-
-#Find files to split
-#extend globbing used to find both tiled and non-tiled files
-curr_dir = os.getcwd()
-os.chdir("curr_dir/inputDir")
-
-#If in sub-dir mode, process the sub-directories instead of the main one
-if use_subdirs:
-    for subdir in os.listdir():
-        recent_dirs=[]
-        recent_dirs.append(subdir)   #pushd
-#        files-glob.glob(
-        files=glob.glob('*'+'.'+component+'?'+'(.tile?)'+'.nc')
-        #files=$(echo *.$component?(.tile?).nc)
-        
-        # Exit if no input files found 
-        if len(files) == 0:
-             print("No input files found, skipping the subdir "+subdir)
-             os.chdir(recent_dirs[-2])   #popd
-             continue
-
-        # Create output subdir if needed
-        os.mkdir(outputDir/subdir)
-
-        # Split the files by variable
-        # Note: cdo may miss some weird land variables related to metadata/cell_measures
-        for file in files:
-             newfile = subprocess.call(["sed 's/nc$//' {file}"],shell=True)
-#             subprocess.call("cdo --history splitname $file $outputDir/$subdir/$(echo $file | sed 's/nc$//')", shell=True)
-             cdo=Cdo()
-             cdo.splitname(input=file, 
-                           output='outputDir/subdir/newfile')
-             #cdo --history splitname file outputDir/subdir/newfile
-        
-        os.chdir(recent_dirs[-2])   #popd     
-else:
-    files=glob.glob('*'+'.'+component+'?'+'(.tile?)'+'.nc')
-    # Exit if not input files are found
-    if len(files) == 0:
-        print("ERROR: No input files found")
-        sys.exit(1)
- 
-    # Split the files by variable
-    for file in files:
-        #newfile=file | sed 's/nc$//'
-        newfile = subprocess.call(["sed 's/nc$//' {file}"],shell=True)
-        cdo=Cdo()
-        cdo.splitname(input=file, 
-                      output='outputDir/newfile')
-        #cdo --history splitname file outputDir/newfile
-  
-print("Natural end of the NetCDF splitting")
-sys.exit(0) #check this
diff --git a/app/split-netcdf-python/meta/rose-meta.conf b/app/split-netcdf-python/meta/rose-meta.conf
deleted file mode 100644
index 316e80e5..00000000
--- a/app/split-netcdf-python/meta/rose-meta.conf
+++ /dev/null
@@ -1,18 +0,0 @@
-[env]
-
-[env=component]
-compulsory=false
-type=real
-
-[env=date]
-compulsory=false
-
-[env=inputDir]
-compulsory=false
-length=10
-title=Directory containing the input files to be split
-
-[env=outputDir]
-compulsory=false
-title=Directory to write the split-out files
-type=boolean
diff --git a/app/split-netcdf-python/rose-app.conf b/app/split-netcdf-python/rose-app.conf
deleted file mode 100644
index b90b0528..00000000
--- a/app/split-netcdf-python/rose-app.conf
+++ /dev/null
@@ -1,4 +0,0 @@
-[command]
-default=split-netcdf
-
-[env]
diff --git a/app/split-netcdf/bin/split-netcdf b/app/split-netcdf/bin/split-netcdf
deleted file mode 100755
index bfcecc35..00000000
--- a/app/split-netcdf/bin/split-netcdf
+++ /dev/null
@@ -1,182 +0,0 @@
-#!/bin/bash
-set -euo pipefail
-set -x
-
-#
-# Split NetCDF files by variable
-#
-# Can be tiled or not. Component is optional, defaults to all.
-#
-# Input format:  date.component(.tileX).nc
-# Output format: date.component.var(.tileX).nc
-#
-
-echo Arguments:
-echo "    input dir: $inputDir"
-echo "    output dir: $outputDir"
-echo "    date: $date"
-echo "    component: $component"
-echo "    use subdirs: ${use_subdirs:=}"
-echo Utilities:
-type cdo
-
-# Verify input directory exists and is a directory
-if [[ ! -d $inputDir ]]; then
-    echo "Error: Input directory '${inputDir}' does not exist or isn't a directory"
-    exit 1
-fi
-
-# Verify output directory exists and is a directory
-if [[ ! -d $outputDir ]]; then
-    echo "Error: Output directory '${outputDir}' does not exist or isn't a directory"
-    exit 1
-fi
-
-# Setup PYTHONPATH and io lists for the data lineage tool
-if [ ! -z "${EPMT_DATA_LINEAGE+x}" ] && [ "$EPMT_DATA_LINEAGE" = "1" ]; then
-    export PYTHONPATH=$CYLC_SUITE_DEF_PATH:$PYTHONPATH
-    export input_file_list=
-    export output_file_list=
-    echo "Set PYTHONPATH and created i/o lists"
-fi
-
-# Find the files to split
-# extended globbing used to find both tiled and non-tiled files
-cd $inputDir
-shopt -s extglob
-
-# If in sub-dir mode, process the sub-directories instead of the main one
-if [[ $use_subdirs ]]; then
-    for subdir in $(ls); do
-        pushd $subdir
-        files=$(echo *.$component?(.tile?).nc)
-
-        # Exit if no input files are found
-        if [[ $files =~ \* ]]; then
-            echo No input files found, skipping the subdir "$subdir"
-            popd
-            continue
-        fi
-
-        # Create the output subdir if needed
-        mkdir -p $outputDir/$subdir
-        
-        # Split the files by variable
-        # Note: cdo may miss some weird land variables related to metadata/cell_measures
-        for file in $files; do
-                cdo --history splitname $file $outputDir/$subdir/$(echo $file | sed 's/nc$//')
-        done
-
-        if [ ! -z "${EPMT_DATA_LINEAGE+x}" ] && [ "$EPMT_DATA_LINEAGE" = "1" ]; then
-
-            epmt annotate EPMT_DATA_LINEAGE_IN_PATH="$inputDir/$subdir/"
-            echo "[DATA LINEAGE] Annotated $inputDir/$subdir/ to EPMT_DATA_LINEAGE_IN_PATH"
-
-            epmt annotate EPMT_DATA_LINEAGE_OUT_PATH="$outputDir/$subdir/"
-            echo "[DATA LINEAGE] Annotated $outputDir/$subdir to EPMT_DATA_LINEAGE_OUT_PATH"
-
-            start_time=$(date +%s)
-
-            for file in $files; do
-                hash_val=$(/home/Cole.Harvey/.conda/envs/bloom-filter-env/bin/python \
-                -m data_lineage.bloomfilter.HashGen $inputDir/$subdir/$file)
-                export input_file_list="${input_file_list}$file $hash_val,"
-                echo "[DATA LINEAGE] Added $file to input list with hash_val: $hash_val"
-            done
-
-            end_time=$(date +%s)
-            duration=$((end_time - start_time))
-            echo "Time spent hashing and creating the file list: $duration seconds"
-
-            cd $outputDir/$subdir
-                start_time=$(date +%s)
-
-                for output_file in $(ls); do
-                    hash_val=$(/home/Cole.Harvey/.conda/envs/bloom-filter-env/bin/python \
-                    -m data_lineage.bloomfilter.HashGen $(pwd)/$output_file)
-                    export output_file_list="${output_file_list}$output_file $hash_val,"
-                    echo "[DATA LINEAGE] Added $output_file to output list with hash_val: $hash_val"
-                done
-
-                end_time=$(date +%s)
-                duration=$((end_time - start_time))
-                echo "Time spent hashing and creating the file list: $duration seconds"
-
-            cd ../..
-        fi
-        popd
-    done
-else
-    files=$(echo *.$component?(.tile?).nc)
-
-    # Exit if no input files are found
-    if [[ $files =~ \* ]]; then
-        echo ERROR: No input files found
-        exit 1
-    fi
-
-    # Split the files by variable
-    for file in $files; do
-        cdo --history splitname $file $outputDir/$(echo $file | sed 's/nc$//')
-    done
-
-    if [ ! -z "${EPMT_DATA_LINEAGE+x}" ] && [ "$EPMT_DATA_LINEAGE" = "1" ]; then
-        epmt annotate EPMT_DATA_LINEAGE_IN_PATH="$inputDir/"
-        echo "[DATA LINEAGE] Annotated $inputDir/ to EPMT_DATA_LINEAGE_IN_PATH"
-
-        epmt annotate EPMT_DATA_LINEAGE_OUT_PATH="$outputDir/"
-        echo "[DATA LINEAGE] Annotated $outputDir/ to EPMT_DATA_LINEAGE_OUT_PATH"
-
-        start_time=$(date +%s)
-
-        for file in $files; do
-            hash_val=$(/home/Cole.Harvey/.conda/envs/bloom-filter-env/bin/python \
-            -m data_lineage.bloomfilter.HashGen $inputDir/$file)
-            export input_file_list="${input_file_list}$file $hash_val,"
-            echo "[DATA LINEAGE] Added $file to input list with hash_val: $hash_val"
-        done
-
-        end_time=$(date +%s)
-        duration=$((end_time - start_time))
-        echo "Time spent hashing and creating the file list: $duration seconds"
-
-        cd $outputDir/
-         
-            start_time=$(date +%s)
-
-            for output_file in $(ls); do
-                hash_val=$(/home/Cole.Harvey/.conda/envs/bloom-filter-env/bin/python \
-                -m data_lineage.bloomfilter.HashGen $(pwd)/$output_file)
-                export output_file_list="${output_file_list}$output_file $hash_val,"
-                echo "[DATA LINEAGE] Added $output_file to output list with hash_val: $hash_val"
-            done
-
-            end_time=$(date +%s)
-            duration=$((end_time - start_time))
-            echo "Time spent hashing and creating the file list: $duration seconds"
-
-        cd ..
-    fi
-
-fi
-
-if [ ! -z "${EPMT_DATA_LINEAGE+x}" ] && [ "$EPMT_DATA_LINEAGE" = "1" ]; then
-
-    # Annotate to EPMT
-    if [ -n "$input_file_list" ]; then
-        compressed_bytes=$(/home/Cole.Harvey/.conda/envs/bloom-filter-env/bin/python \
-        -m data_lineage.bloomfilter.StringCompression "${input_file_list}")
-        epmt -v annotate EPMT_DATA_LINEAGE_IN="${compressed_bytes%*,}"
-        echo "[DATA LINEAGE] Annotated input files to EPMT_LINEAGE_IN"
-    fi
-
-    if [ -n "$output_file_list" ]; then
-        compressed_bytes=$(/home/Cole.Harvey/.conda/envs/bloom-filter-env/bin/python \
-        -m data_lineage.bloomfilter.StringCompression "${output_file_list}")
-        epmt -v annotate EPMT_DATA_LINEAGE_OUT="${compressed_bytes%*,}"
-        echo "[DATA LINEAGE] Annotated output files to EPMT_LINEAGE_OUT"
-    fi
-fi
-
-echo Natural end of the NetCDF splitting
-exit 0
diff --git a/app/split-netcdf/meta/rose-meta.conf b/app/split-netcdf/meta/rose-meta.conf
deleted file mode 100644
index 316e80e5..00000000
--- a/app/split-netcdf/meta/rose-meta.conf
+++ /dev/null
@@ -1,18 +0,0 @@
-[env]
-
-[env=component]
-compulsory=false
-type=real
-
-[env=date]
-compulsory=false
-
-[env=inputDir]
-compulsory=false
-length=10
-title=Directory containing the input files to be split
-
-[env=outputDir]
-compulsory=false
-title=Directory to write the split-out files
-type=boolean
diff --git a/app/split-netcdf/rose-app.conf b/app/split-netcdf/rose-app.conf
deleted file mode 100644
index b90b0528..00000000
--- a/app/split-netcdf/rose-app.conf
+++ /dev/null
@@ -1,4 +0,0 @@
-[command]
-default=split-netcdf
-
-[env]
diff --git a/flow.cylc b/flow.cylc
index 1bd0d003..b6bbb8d4 100644
--- a/flow.cylc
+++ b/flow.cylc
@@ -620,28 +620,33 @@ rename-split-to-pp-regrid<regrid_static> => remap-pp-components-static => combin
 {% endif %}
 
     [[SPLIT-NETCDF]]
-        pre-script = mkdir -p $outputDir
-        script = rose task-run --verbose --app-key split-netcdf
+
         [[[environment]]]
+            {# $date was used as an input arg in the earlier version of  #}
+            {# split-netcdf without getting referenced in the script itself. #}
+            {# I think it's a reference to an older script that got removed in #}
+            {# the first round of cylc rewrites; keeping it here in case #}
+            {# we turn out to need it during the user testing. #}
             date = $CYLC_TASK_CYCLE_POINT
 
 {% if DO_NATIVE %}
     [[SPLIT-NETCDF-NATIVE]]
         inherit = SPLIT-NETCDF
+        script = fre pp split-netcdf-wrapper -i $inputDir -o $outputDir -s $history_file -c $component -y $CYLC_WORKFLOW_RUN_DIR/{{ YAML }}
         [[[environment]]]
             inputDir = $CYLC_WORKFLOW_SHARE_DIR/cycle/$CYLC_TASK_CYCLE_POINT/history/native
             outputDir = $CYLC_WORKFLOW_SHARE_DIR/cycle/$CYLC_TASK_CYCLE_POINT/split/native
-            component = $CYLC_TASK_PARAM_native
+            history_file = $CYLC_TASK_PARAM_native
 {% endif %}
 
 {% if DO_REGRID %}
     [[SPLIT-NETCDF-REGRID]]
         inherit = SPLIT-NETCDF
+        script = fre pp split-netcdf-wrapper -i $inputDir -o $outputDir -s $history_file -c $component -y $CYLC_WORKFLOW_RUN_DIR/{{ YAML }} --use-subdirs
         [[[environment]]]
             inputDir = $CYLC_WORKFLOW_SHARE_DIR/cycle/$CYLC_TASK_CYCLE_POINT/history/regrid-xy
             outputDir = $CYLC_WORKFLOW_SHARE_DIR/cycle/$CYLC_TASK_CYCLE_POINT/split/regrid-xy
-            use_subdirs = 1
-            component = $CYLC_TASK_PARAM_regrid
+            history_file = $CYLC_TASK_PARAM_regrid
 {% endif %}
 
 {% if DO_NATIVE %}
@@ -652,7 +657,7 @@ rename-split-to-pp-regrid<regrid_static> => remap-pp-components-static => combin
     [[split-netcdf-native<native_static>]]
         inherit = SPLIT-NETCDF-NATIVE, <native_static>
         [[[environment]]]
-            component = $CYLC_TASK_PARAM_native_static
+            history_file = $CYLC_TASK_PARAM_native_static
     {% endif %}
 {% endif %}
 
@@ -664,7 +669,7 @@ rename-split-to-pp-regrid<regrid_static> => remap-pp-components-static => combin
     [[split-netcdf-regrid<regrid_static>]]
         inherit = SPLIT-NETCDF-REGRID, <regrid_static>
         [[[environment]]]
-            component = $CYLC_TASK_PARAM_regrid_static
+            history_file = $CYLC_TASK_PARAM_regrid_static
     {% endif %}
 {% endif %}
 
diff --git a/site/gaea.cylc b/site/gaea.cylc
index 3a939126..1af504ec 100644
--- a/site/gaea.cylc
+++ b/site/gaea.cylc
@@ -68,7 +68,7 @@
 {% endif %}
 
     [[SPLIT-NETCDF]]
-        pre-script = module load cdo nco && mkdir -p $outputDir
+        pre-script = module load fre/{{ FRE_VERSION }} && mkdir -p $outputDir
 
     [[RENAME-SPLIT-TO-PP]]
         pre-script = module load cray-hdf5 cray-netcdf cdo fre/{{ FRE_VERSION }} && mkdir -p $outputDir
diff --git a/site/ppan.cylc b/site/ppan.cylc
index b6439796..26b2727b 100644
--- a/site/ppan.cylc
+++ b/site/ppan.cylc
@@ -69,7 +69,8 @@
 {% endif %}
 
     [[SPLIT-NETCDF]]
-        pre-script = module load cdo nco && mkdir -p $outputDir
+        pre_script = module load fre/{{ FRE_VERSION }}; mkdir -p $outputDir
+        {# pre-script = set +u; module load miniforge; conda activate fre-cli; set -u ; mkdir -p $outputDir #}
 
     [[RENAME-SPLIT-TO-PP]]
         pre-script = module load netcdf-c cdo fre/{{ FRE_VERSION }} && mkdir -p $outputDir
diff --git a/site/ppan_test.cylc b/site/ppan_test.cylc
index 3ed31bf7..558c0361 100644
--- a/site/ppan_test.cylc
+++ b/site/ppan_test.cylc
@@ -109,7 +109,7 @@
 {% endif %}
 
     [[SPLIT-NETCDF]]
-        pre-script = module load cdo nco && mkdir -p $outputDir
+        pre-script = module load fre/{{ FRE_VERSION }} && mkdir -p $outputDir
 
     [[RENAME-SPLIT-TO-PP]]
         pre-script = module load netcdf-c cdo fre/{{ FRE_VERSION }} && mkdir -p $outputDir