I can call my T between sessions, and it doesn't have to be when I'm in crisis. I can leave a message, and if I want a call back I ask. If it relieves me to just leave the message, then I don't ask for a call back.

I talked to T once about calling and asked what patients call about. She said sweetly 'anything'. The need doesn't have to qualify, or pass any test.
I told her also that I was afraid I might call too often, and she said to not worry about that, if that happened, then we would talk about it.