Been there, done that! Once I decided that I needed this woman (my T) to help keep me sane, I allowed myself to email her "x" amount of times during her vacations. She always responded and sometimes even emailed me first.

I also figured she wouldn't have offered to let me email her if she really didn't want me too, so the same should hold true for you. Your T is welcoming your emails so he wants to support you while he away. If sending him emails will help you, I vote you go for it!