Apple has posted an announcement on its developer site for both iOS and Mac developers noting that it will reset all iCloud backup data on September 22nd. “On Thursday, September 22, the iCloud Backup data will be reset.
Backing up to iCloud or restoring from an iCloud backup will be unavailable from 9 AM PDT – 5 PM PDT,” the message reads. “If you attempt a backup or restore during this time, you will receive an alert that the backup or restore was not successful.
After this reset, you will be unable to restore from any backup created prior to September 22. A full backup will happen automatically the next time your device backs up to iCloud.” Registered developers have had access to iCloud for testing purposes during the iOS 5 beta period, as the service will launch alongside iOS 5 this fall.