there is no such thing as 'Day after Groundhog Day'.
That's the entire point.
Has somebody slipped something into the coffee tonight?
My guess is, if it was Groundhog Day for real, every day would be Feb 2nd, therefore airing the film on a loop for subsequent days would also be valid.
The flaw is that only the subject of the loop (Bill Murray's character Phil) is aware of it and is the only one repeating the day, for everyone else there is only one Feb 2nd, therefore Sky would only need to schedule it on Feb 2nd, the subject/Phil would just see the same exact showings over and over...
Of course if Phil was watching the film himself, he'd obviously realise how to break the loop a lot quicker.