Yes, he will let you know when the best time to visit would be. It is best to wait until he has phased up and is able to leave the base before planning a visit.
When I was in A school 20+ years ago, of course studying should have been priority but evenings and weekends were free to do as we wished. There was usually something going on, on post and off. Things seem to have changed a lot but he should be able to call you and will probably be able to have his phone and/or computer but I'm not sure what their rules are on that as we did not have those things back then.
I went to my A school there even longer ago, much stricter now.
Here are the current phases if you are curious: