Valmont,
There were a couple of instructors who made the move from QAC to QR this year, but I wouldn't base the decision on whether to join the college on that.
In order to jump from one sponsor (employer) to another here you currently need a letter of no objection and whether you get this or not depends on a lot of factors pretty much all of which are out of your control.
Without the letter then you must leave the country for 2 years before you can apply to another employer...........
So yes it is possible, but from what I've seen it is the exception rather than the norm.
Chinchilla.