Hi Justin,
Very probably the same form I filled out a few weeks ago. I said that I'm TG under hormone, surgical and psychiatric therapy to transition to my female sex. You have to give a 'reasonable' explanation, they will not take anything less than what they consider a valid reason. Because I don't like my name is rejected. They also reject in rote. The first letter says (eg) not a valid reason. You answer. Next letter says, no proof of residency, you answer, next letter is 'incorrect fee. etc. Then it is a minimum of 20 days when they can't find another excuse.
The people at BD&M were very pedantic and wanted everything totally clear. They asked for several months bank statements and/or Rate statements to prove I've been living in Adelaide for the last three months. Even though they had my driving licence, with my home address, passport etc. So make sure you include everything and get everything signed off by a police person or a JP. They seemed pretty keen to find ways to not process it if at all possible.
And congrats on a big step!!
That means here are three of us in NT and SA getting our name changed, as Kelly was getting hers as well.
Def have to have a party

Cindy