@United84
There are three different treatments or ways of working for Sundays throughout the rail industry:
'Voluntary' - There will be Sundays in the base roster, as overtime, but you can say you are "not available" with a certain amount of notice. Then it's the Roster Clerk's issue to find someone else to cover the job for that Sunday - there are usually people who will work an extra Sunday in normal circumstances.
"Committed" - If you don't want to work a Sunday in the base roster, YOU have to find someone else to work it for you, or you HAVE to come in and do it, even though it is overtime. Enforced overtime.
"Sundays in the working week" - Sunday is a normal day, not overtime, and if you want a Sunday off, you'd apply for annual leave for that day. This would have a different rest day pattern as for every Sunday at work there would need to be another day of the week as a rest day.
At the moment, at West Midlands, Sundays are voluntary, meaning they are overtime if you work them, but you can have one off easily.
If they move to committed, then you have all the responsibility of finding cover, which for the Sunday between Christmas and New Year might well be a hassle for example. Mother's Day, Father's Day, Easter Sunday - you have the hassle if you want the day off and the base roster has you down to work.
As Sunday would still be outside the working week with "committed" and therefore still completely overtime, the rest day pattern for the other days of the week would still stay the same.
Nothing has been agreed about any changes to current situation yet.