Oh I just assumed that What Have I Done? was set during the time that Jack lived through the 20th Century. Still, in the Post-Children of Earth solo adventures Gap is just as easy a placement.
Thanks for your contributions meddlingmonk.
Yeah I was thinking that when I looked up the story details for 'What Have I Done'. I suppose Captain Jack had the ability to time travel when he used the vortex manipuator at the end of 'Children of Earth'.
Does anyone know where 'Piece of Mind' takes place for the Sixth Doctor?
As discussed on the Sixth Doctor's Timeline thread, it could fit quite neatly just before The Marian Conspiracy.
Just before the Marian Conspiracy could be perfect; he goes into the coma at the end of this and arguably starts a new life with Evelyn in the next one.