WOW! She is so cute! This should be a snap for her. I hope it goes as easily and smoothly as it can for her and you.
When you ask about HRT time line. Do you mean literally what changes she can expect and when or when will most of the changes be done? Two things were mentioned so far:
1 It is different for everyone
2 Usually starting closer to puberty tends to have quick and better effects.
I am only just starting this very soon myself. So I do not have the ability to speak from personal experience. However, there do tend to be specific things that happen in a typical order within a given time frame. I think I can honestly say that while some are able to rush through in under 2 years to do a full transition many seem to take 3-4 years and by then the HRT has evened out but there may still be additional changes. Please correct me, if I am giving faulty information, anyone.
Oh, and it is very tempting to rush ahead into everything as it all seems to be exciting and so right. If you can encourage her to take her time and feel and think through things. I don't remember seeing whether she is doing therapy at university. If she is not, she really should. I imagine there may be fewer bottoming out moments.
I think I can speak for most of us when I say things can be going very well, then crash. She may be moving along with no problems from others. However, a voice or feeling in the head(or from someone else whether thinking about it or not) may bring about huge depressive moments. I think HRT can cause some mood shifts(am I wrong about that?). Many of us will have crashing points. Doubts like: am I doing the wrong thing; I am just a fake; I hate how I look; I don't pass, everybody knows; I am a freak and will never fit in; why don't they have those shoes in my size(okay, you caught me. maybe not that one)... She may just need her friends, a supportive parent or to visit that therapist. We usually can bounce back without too much problem but it can seem very dire and dreadful at the moment. The hard part for you might be that she may more want/need a friend.
Have to get back to work.
We are all here and pulling for you and she.
With warmth,
Joanna