I assume you meant "sleeping"? And snakes brumate, they don't hibernate.

Anyway, as to how long to wait before offering food (& assuming you're not handling at all), I'd see how the snake acts in 4 days- if he seems to be looking for food (& by that I mean he's watching from the doorway of his hide- most likely- & in the evening hours- and NOT "cruising the enclosure"- you might go ahead & offer him food, but it won't hurt to wait a few more days either- the main thing is to wait until he's really ready to accept food. Failure is no fun. Your temps sound fine, btw-