Congrats, that's so great.
Just as a head's up though, even when your parents are in your corner and everything seems great at first, there can be times when the "getting used to it part" can be a little awkward or such, and they might not always act exactly like they used to or be 100% understanding, even if they're 100% supportive. That might not happen for you, but I just wanted to share so that if it does, you'll expect it in advance and know that it doesn't negate their support, it just means this is a wild ride with lots of complex issues, and most people don't get from start to finish without some bumps along the way, no matter how smooth the path looks from the outset.
My mom (for all intents and purposes my only parent... sort of. long story) has been incredibly supportive, right from the beginning, and continues to be, but there have still been times that her lack of knowledge about trans issues, or just her being used to who I was for the last 30 years, have caused some awkward (for lack of a better word) comments or situations these past few months. I do know that she loves me and supports me (and thinks of me now as her son, etc) but she's not even aware sometimes of the things she says and how inappropriate or just "not on target" they are. I know I'm being about as clear as mud, but that's the thing, this situation can sometimes be like that.
Okay, how about an example, since I'm clearly not doing a very good job explaining this: Until I had talked to my mom about what the surgery options were for FTMs, she was under the mistaken assumption that it was the reverse of what is available for an MTF. She tells me the other day, that she went around telling our family and friends (meaning to be helpful and such) that they take the stuff that's there, turn it outside, and voila! ... {sound of crickets chirping} I was not really impressed because: A) she was perpetuating a myth and giving even more people "improper" info about trans issues, B) she was talking about my transition to people that I'd want the opportunity to explain it to myself, and C) She was talking to my friends and family about my crotch! Ugh, mom!!!
So, like I said, I educated her about the surgery options, and also kind of nicely explained that some things are better left for me to tell people in my own way and my own time. These were all people who already knew about me being trans, but still... it just wasn't what I wanted them to hear or how I wanted them to hear it.
And it's not like she wasn't being supportive, it's just that there are ups and downs with supportive parents too. Or like when she's so enthusiastic to show how supportive she is that she OVER uses male titles and pronouns and stereotypes to be all like "see, see, I'm supportive" and it's just like "mom, relax and just be yourself". Did you ever see that episode of Dharma and Greg where Dharma was being condescending to little people, but she really meant well and was trying to show how accepting she was? It's like that. It's like making *too* much of an effort, if that makes any sense.
Anyhow, again, not saying it *will* be like that for you, just that I wish someone had told me "even if your parents are supportive, there may still be snags along the way" so that I knew to expect it, and that it doesn't change how they really feel. If that makes any sense at all...
Aha, I found the clip! (You can skip to around 2:00 to see the part I'm talking about).
Dharma & Greg 4x21 Pride And Prejudice Clip1