[regularfry]

I'd come at this from the point of view that no, holiday means no contact.

It is not "normal" for managers to be available to be called while they're on holiday. When I've been in management roles the rules have been the same as non-management rules. Holiday is holiday: you're not there.

What that means is, if your manager needs support while you're away, you and he need to have a discussion about what cover looks like such that you personally don't need to be there. What can you delegate up or down? Is there a peer you can hand some responsibilities off to temporarily?

If he's not willing to have that discussion at all, that's a real problem, but I'd approach it as a problem to be mutually solved.