Maintenance start and end times differ from UI and Email

[AshleyDodd]

Describe the bug
If you create a maintenance period with a start time of 0800, in the email it will say 0700. This is the same with end times, If you have it ending at 1200, it will say 1100.

To Reproduce
Steps to reproduce the behavior:
Create a maintenance period.

Version
4.0.22

Environment
Docker

Database
SQLite

Expected behavior
For the times to show correct in both places.

Screenshots
UI:

Email:

[namatery]

I traced this to different timezone contexts in the UI and email formatter.

The maintenance form converts the browser-local datetime-local value to a Unix timestamp. The email later formats that timestamp in the Node server timezone, which Kener explicitly sets to UTC. For example, 08:00 BST is stored as 07:00 UTC; the UI converts it back to 08:00, while the email prints 07:00 without indicating UTC. This also explains why the difference is exactly one hour and may disappear outside DST.

This does not appear to be SQLite-specific.

@rajnandan1, which behavior should notifications use?

1. Always display UTC and label it explicitly — small, unambiguous change.
2. Add/configure an IANA timezone for maintenance notifications — allows emails to match the intended local schedule but requires deciding where that timezone is stored.

Subscriber records currently have no timezone, so matching every recipient’s browser-local display is not possible without additional data. I can prepare a fix once the intended behavior is confirmed.