We've just made the move back after 8 years. Our little one is not school age yet so can't help with that sort of thing but my best piece of advice would be, if you know where you're going to be staying (even if it's just with family temporarily) try to get a few things with an address on. We had to show proof of address to register with a GP and various other things. If your UK driving licence isn't current try to sort that before you return (I found the people at the DVLA really helpful when I called) as many insurance companies will charge you a lot more, or refuse to insure you on an Aus licence (this doesn't apply to hiring a car). These sorts of things just make things quicker and less frustrating when you're already busy & jet lagged! We're currently trying to rent a house which is proving problematic without proof of income...good luck!