Hmmm ... let me venture a toe out in traffic here. There's no debate here about me being post-op; I've had no surgeries, no real life experience (as female), no hormones, no therapist. I guess it's not rocket science to list my understanding of a course of action, at least for me:
A. Keep my marriage together.
B. Help my wife deal with this (and she is very supportive, but it is
still a
real real life experience).
C. Consultation with a Therapist.
D. Sufficient understanding of my condition to proceed or stop.
E. Electrolysis and/or other hair removal.
F. Hormone treatment.
G. Coming out to certain family and friends.
H. Coming out to job, or trade it in for either a more accepting work atmosphere,
or in a bit over a year I qualify for early Social Security (my pink parachute!) >

I. Two years Real Life Experience.
J. Orchiectomy.
K. S.R.S.
L. F.F.S.
M. Sit back and enjoy the results. Well, not actually.
Hey, lined out like that it doesn't sound so hard (Susan Kay ducks many thrown objects from the forum, leaping very unlady-like behind the couch.)
So, anyway, where in this list would I consider myself Post-Op? Frankly my dear, I don't give a damn! For me, life has never been a project to be completed; I would not ever expect to complete transition, even if I was starting at puberty; it's a lifetime experience. But, to answer the original, at first glance, innocuous, question, I think it applies to any person that has had one set of genitals removed and at least minimal genitals of the opposite sex installed TO THAT PERSON'S SATISFACTION!
Susan Kay
Just reviewing my list, and this is what I hate about lists, I forgot the legal aspects. I'll shoe-horn them in there some place, keeping in mind that I was born in Ohio, and I understand that they don't allow that appropriate and humane change.