Most nights you're allowed two or three hours sleep - that counts as time off I suppose.
Seriously; you 'might' get an hour in the NAAFI every evening, a long weekend after 5 weeks followed by free evenings and weekends depending on the requirements of the training programme (and how much you firk up).
Don't expect much free time during your first weeks of training. You won't have time to breathe.
When i went through Pirbright (a few years ago now) we got a long weekend after week 6 (drill test 1) but we werent allowed off camp at the weekends or the evenings.
At Catterick we had most weekends off but having to be back at a certain time on Sunday etc. While we in theory had the evenings free after shining parades, swabbing parades and other various **** arounds you would be lucky if you got half an hour to nip to the naafi before it shut.
First 6 weeks you get Monday to Friday 20:00 off
Sat & Sun you train finishing about 16:00 Sunday (might knock off early if it rains)
After this you will get a date to attend two straight weeks where as long as you pass the running the rest you can be w4nk at (marching, kit etc) everything else
Then a pass out and your away
You did say you were joining the TA didn't you ?
As an Aside
RAF Basic consists of Mon - Fri 08:00 - 16:30 Friday finish 11:30
RAF Ragiment Mon - Friday 07:30 - 17:00 Friday 15:00 due to their special status