Hi, I personally would wait and if you could manage it, book them for a week after the tenants moved in, just in case there are any issues that you need to deal with in the beginning - unless of course you have a key holder/caretaker minding it for you. Also if you wanted to book now, check with the airline how much it would cost to change the tickets. I changed mine when leaving Perth, bought it forward 3 days, and it cost an extra $300. I didn't care as I had urgent family problems and I had to leave immediately, but that wouldn't suit everyone. Good luck on your move.