Wirelessly posted (BlackBerry: BlackBerry8530/5.0.0.1030 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)
It's possible, but not assured.
Are there AA partners that fly your route that cannot show award availability on aa.com? (Award availability on about half of AA's partners cannot be checked on aa.com.) A call to AA might turn up availability for your desired date on one of those partners.
If you book a less desirable flight now at the SAAver level, and your preferred flight later becomes available at the SAAver level, you can switch flights at no charge as long as the old and new itineraries contain only oneworld carriers.
What route are you trying to fly?