I know any pre-ordered but yet delivered customers qualify for the $500 & Service rebate offer.

If your RX-8 is delivered before Oct 1, I assume Mazda will make you sign the release for Rebate/Service when you can take ownership to ensure you have no grounds to make them buy it back. Correct?

Yes. You sign two one says you know about the HP change and the other says yoy get $500 debt card and free maint. I picked mine up yesterday. I love the car and am very happy with the maint. As I understand it it only ECU change (remember the port stickers). Use your $500 to have it reprogramed if you can bear to park it for a week. I can't yet.