John,
The freeze for new cadets is for 5 years, but if the fleet is reducing or if you are needed elesewhere then you may find yourself shifted inside that time. Every year you get to bid for a new posting and you are encouraged to bid even if you are within a freeze. Reason is that if they have to move you then they would rather send you somewhere that you want to go.
On shorthaul we do a variety of daytrips, and 2,3,4 or 5 day trips. On average you will spend about 7 nights away from home per month, although this can be adjusted up or down according to your personal preference. Typically a nightstop will be either an "early " or "late". That is you either arrive mid afternoon and leave at the crack of dawn the next day or you arive in the dead of night, but leave sometime after lunch the next day.
Nightstops do vary in their duration, but on most there is the chance to get out and about and see something of the city. Accomodation for flight crew is generally in the centre of town and of a high standard.
On longhaul you get longer nightstops (usually at least 24 hours), but I haven't graduated to those dizzy heights yet so I couldn't tell you much more about that lifestyle.
Hope this helps or at least whets your appetite!
eeper