Hello Ivor,
You will get your 28 days when at unit which you can request to be taken at times that suit you. You will have to deconflict your leave with training courses which require a lot of resource and will have been booked in advance of your arrival.
I'm sorry that I was not as fast as usual but I can asure you I am still reliable!
1985 is correct with the shift pattern, 6 on 4 off, this is at Area units, the Airports can be quite different.