I have had my shift brought forward by one hour do I need to sign a new contract I know if I objected they can give a months notice they are changing it.
I am sure they can just issue a letter confirming the change. I think it would be good practice to ask you to sign it but I think there is a good chance they could get away with just issuing it, putting the onus on you to write with any objection. Buenchicu will know and there are some experts in that area who will see this hopefully