Wasn't the renewal deadline in January (the 26th is what they told me at least)?
I would say if you buy season tickets anytime before the season, including August, that you have still had season tickets in consecutive seasons and really should get the points.
If you haven't renewed by the deadline, the ATO would have the right to yank seat locations, but I'm actuality, they might hold them up to closer to the re-seat event just to try to get people to re-up.
Another thought on this is that consecutive years points sre pretty small. If one wanted to chose when to go, donating $100+ to athletics yearly would ramp up priority points much quicker... 5x quicker to be exact. Not to give people excuses to bail, but donations of $100, or even $500, per year + single game tickets for the ones you can make could actually be cheaper than buying season tickets.