As always, thanks everyone for the insights and advice. I decided to contact my STBXW with this reply to her request.
"I am going to have to get back to you about D birthday. You probably shouldn't make any concrete plans until I know what our schedule of events will be. I will let you know as soon as possible."
She went on to make a point that we will be sharing time with daughter for a long time, years and years. I said that I agreed, and that as soon as I knew what we were doing I would make some arrangements with her to see D.
