"Fellows currently starting command course joined 96-97"
No one who joined in 1997 has started a command course (or been assessed for command) on the Pax fleet.
"The current variables including command failures and Cat B'd SFOs means that time to being considered for command is around 7yrs."
Assuming being "considered for command" means command selection panel, then the time is currently running at 9+ years. i.e. The first guys who joined in '97 are being assessed in Jan 2006 for a pax command, the course date of which is determined by numerous variables.
"If Cat A (and passing the course) time to command is set to stabilise at approx 8yrs from time of joining."
And how exactly did you work that little gem out? You haven't been listening to Don't Know Hau have you?