I think it is wise to not get into history if your T is going to be away again. If things come up though just come and vent whatever you need to here where others can help ground you and support you.

I know about losing time, I had done that myself and still do if I experience a bad trigger. However, I have come to slowly understand that as hard as it is I tend to learn something from it when it happens. I do think it is important to have a T there to help. Your T seems to really understand a lot about PTSD, that is good, some of them don't and it's really important someone works with someone who does.