Understand summers are "crazy busy", winters quiet
Busy depends what you are used to, but yes, they can be hectic. There is no roster pattern (fixed or otherwise), and you can expect plenty of changes to the published versions. Days off don't change once published, but the duties either side can (and do) change.
Typically 2 sector days.
How busy you'll be is base dependant. If you are at a base with lots of trainers, I don't imagine you'll be getting much flying at the moment - or next year with the volume of recruitment planned.
amount of time sitting around on the ground etc
If you mean on turnarounds, little if any. An hour max, usually 30 - 40 min turnarounds. Unless you are on airport standby, once you're home, you're done.
Winters are quiet, expect plenty of home standby, and probably airport standby if MAN or LBA based.
Heard rumours of Airbus orders. Any update on this?
No update, They're still looking at different options, but there is an upgrade program on the cards for the winter to modernise some of the existing fleet.