They only 'move you round the bases' if the company requires it (ie don't give you your first choice initially, then allow you to voluntarily move to somewhere more preferable)- I certainly got my first choice base the day I joined - others have gone to ABZ until openings occur where they want to go.
That said, there is occasionally a requirement to nightstop at other bases for a few days at a time to covers gaps due to leave etc, possibly once a month or so. Not quite the same thing as moving all around the place but possibly what your contact was referring to. (Also move round bases during line training - but that should be expected really!)
Basing is done on a seniority basis.
WX Man: How far north does your girlfriend live? GLA is quita a small base and EDI is v popular. ABZ would probably come your way if you wanted it though. (Having said that any base could be available)
Good luck anyway!