Yes!! Whenever you are staying on property (even if you did not have the
DDP), you could make ADRs for up to 10 nights of your stay, 180 days before you check in. So you could book all 6 nights' worth of ADRs in one phone call and not have to call back everyday. Just have your reservation number handy when you call.
So, for July 18th, you will have to count back 180 days. It will be in the middle of January some time. I did mine then last year for our trip which started July 13th 2008. There are some good ADR calculators out there. Try all ears net.