This hasn't actually happened yet but we're trying to pre-empt what may well happen so we know what rights DH has in advance.
Currently DH works 42.5 hours per week Monday-Friday plus 4 hours on a Saturday every other Saturday.
Regarding the Saturday and holidays etc how they tend to work it at at the minute is that they swap when each other are on holiday so they both end up working 26 Saturdays a year.
Anyway the other person who covers the Saturdays is possibly being made redundant and we are thinking its a possibility that DH may be asked to cover every Saturday which we don't want him to do. It basically means we can never go away for a weekend/ a holiday of longer than a week etc etc.
if asked can he just turn it down flat and say no?
Because of the set up which I won't go into detail on I don't think the people dealing with the redundancies have even realised this is going to be a problem but obviously at some point someone in charge is going to realise "ok so no one is in tomorrow" and can they then insist that DH covers. DH contract says that reasonable overtime is expected.