Canuck,
I got my offer in November, but there's a few people that started in February and got their offers after me. For various reasons, it took just over 3 months for CASA to issue me a class 3, so you really have to chase them and your DAME up. CASA won't bother to contact you if they're missing a bit of paper work.
As far as R&R before you start, I finished my last job at Easter and I've been packing and fixing up stuff around the house ever since
Our break will be the drive down to Melbourne.