Hi grelliot,
I must admit I'm in two minds about it while you are still going through the motions of transitioning.
To some degree depending on how the relationship develops I would think there would be a time and place to discuss this matter, but not first. I'd look at the compatibility of you both first, develop some trust between yourselves and then when you start getting into deeper relationship matters, it may be prudent to discuss it. After all, as you are pre-T and most other things, no doubt, you may not be that committed. I don't know. Only you can answer that question.
Certainly should you later fully transition, assuming you start a new relationship with someone else, I don't believe it is anyones business to know what medical procedures you have been subjected to. My interpretation of having fully transitioned means your gender in congruency has been corrected, making you now your proper gender and you are no longer considered transgendered. In much the same way as everyone else who has had surgical procedure to correct ANY sickness or disease, like cancer or bone fractures etc. What classification are you going to give to a woman who has had a hysterectomy? How about a "woman". What about a man who has had his prostate removed. How about a "man"
Why therefore maintain a outdated label of "transgendered", on a MTF after they have had GCS? After all, isn't that what GCS stands for? Gender CORRECTION surgery.
Please note this is my own personal opinion, and it will be the attitude I will assume post surgery.
Hope things work out for you both, and you are able to find your own solution, that you are comfortable with.
Be safe, well and happy.
Lotsa huggs
Catherine