(((Hugs to all))) Please do discuss this important issue with your respective Ts! They either have a policy or need to have one. If they will make arrangements for you specifically, according to your need, then see if they will.

My pain therapist usually calls within 5 minutes, if he's not in session. Otherwise, he calls within an hour. This isn't for pain management, but to call and check and make arrangements to talk me through pain if I need that (later.)

I know he isn't the usual, but certainly no longer than the end of the day is acceptable, imo, for therapists.

My T has said that if he doesn't call back, to assume the call was dropped or lost somewhere along the lines, and to call again! Discuss this idea with your Ts also. No reason to be anxious over something that a T probably has a rule/guide about.