Yeah, seeing the scare quotes in the thread title gave me pause about what the possible intent of the OP was.
@Ponderoid and @BippityBoppityBoo, my use of the quotes may be incorrect (and I have an English degree - obviously expired 
). I was using them to reflect the specificity of the type of transition for brevity in the thread title. I didn’t intend any negativity.
Good point. I’ve just edited the title.
Thank you
An example from real life for a change-
I wokr in a virtual call center. Occasionally, I will misgender a caller. When I accidentally call a cis man ma’am, they get extremely angry, When I accidentally misgender a caller with an androgynous voice (often a trans person), I apoogize. They say it is no big deal. We move on with the call.
The same is true here.You started this thread because you want to do the right thing and avoid causing social awkwardnes or harm. If you make a mistake now and then, it is no big deal and we can move on.
On social media, yes, people do this all the time.
At work, we had a company meeting where all the non-binaries/trans/etc. said it’s okay to ask out front, “How do you prefer to be addressed?”
I think it’s ok to ask for anyone, right? If your email reads David but you’d rather be called Dave, you can either tell me, or I can ask, and you end up being addressed as you prefer.
I regularly ask people their preference. What surprises me is how often cis people are surprised that I even ask, but they do seem rather pleased when I do. I mean, it’s their identity, if I’m meeting them for the first time, their name could be anything at all, who am I to insist otherwise? I think it’s rude to assume Alexander goes by Alex or Jennifer wants to be called Jenny.
Naturally this extends to trans people. I’ll call you whatever you want, it’s all good.
Sounds like a high school reunion/date. I would advise clarity either way.