probably only around a month, remember that you get long weekends. Not all go home though during these weekends. Plus you can't always depend on having these weekends off, as someone in the troop may screw up and everyone has to stay on camp.
With you being in Glasgow, you'll probably have to use one of your travel warrant via exeter airport. I think they still fly to Glasgow 1 1/2 hours.
All the best
GW