She is canon. She was mentioned - or perhaps even briefly seen, I'm no longer sure - in the Tenth Doctor special, "The Christmas Invasion", and a similarly named character (or perhaps the same one, the TARDIS wiki doesn't tell) is in one of the books.

And I completely agree with you (and with Hannibal Smith) about a plan coming together. Boy, did I love the original A-Team! That was one fun series. Mum and I watched it religiously on German TV and laughed our heads off.