Apple on Monday began reminding some iCloud users that they will soon lose the 20GB of free storage they'd received when they migrated from MobileMe.
The company has notified iCloud customers via email that the 20GB will expire Sunday, Sept. 30.
The move only affects users who had previously paid for MobileMe, the synchronization and storage predecessor to iCloud. While iCloud is free to all Mac and iOS device owners, MobileMe cost $99 annually for, among other things, 20GB of online storage space.
During the switch from MobileMe to iCloud -- a process that started in 2011 and ended June 30, 2012 -- Apple offered an additional 20GB of storage to MobileMe subscribers as a way to temporarily tide them over. The 20GB was atop the standard 5GB all iCloud users received as part of the free package.
Now Apple is taking away the 20GB, telling customers that to keep it they must fork over $40 a year.
"Your iCloud storage will be reduced to 5GB on 09/30/2012," Apple's email stated. "However, you are currently using more than 5GB. Unless you take action before your downgrade takes effect, backups to iCloud will stop, and apps will no longer be able to save documents to iCloud."
Apple instructed customers to either free up enough storage space to drop under 5GB, or pay up to keep the extra 20GB.
The end of the free storage ride had originally been set for June 30, 2012 -- the date MobileMe went dark -- but in May Apple extended the deal by three months.
Users who want to retain the 20GB must pay $40 per year to upgrade (to 25GB total; the free 5GB plus the 20GB). Apple also offers 10GB additional for $20 and 50GB for $100.
Apple's 20GB and 50GB prices are four times what Microsoft charges for extra Skydrive storage. Skydrive allots 7GB of free storage, then charges $10 per year for 20GB more and $25 for an additional 50GB. Microsoft also has a 100GB plan priced at $50.