Sorry this may be long.
I work p/t, three days. Last year my workplace did a 90 day consultation and brought in a new set of rota patterns. They made a pattern for me as I have limited access to childcare at weekends and after hours.
The terms and conditions of the new pattern stated that full timers were expected to work up to 5 out of every 8 weekend shifts, pro rata for pt staff. 3 days a week = working 4 out of 8 shifts, eg equivalent of every other weekend. Quite a lot, but do-able.
New pattern was working fine. However as a whole, they had badly understaffed the weekends and evenings. They have now decided that everyone will work 5 out of 8 weekend shifts, even if they only work 15hrs a week.
This is a nightmare for me(and several colleagues, esp those who share residency of children every other weekend) I understood that contractual matters were robust, eg couldn't be changed without our agreement.
Can I do anything about it? I just cannot work what they are insisting I must work.
I can apply for a FWP but frankly I know it will be declined, they have just turned down a large batch as a group (although I understand they are meant to be considered on an individual basis)