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Back when iCloud replaced MobileMe in 2011, Apple gave paying MobileMe customers an additional 20GB of iCloud storage to thank them for being loyal customers. The free storage was supposed to end in September of 2012, but Apple ended up offering it for another year. Now, Apple has sent emails to former MobileMe customers informing them that the free storage is coming to an end on September 30, 2013.
As a thank you for being a former MobileMe member, you received a 20 GB complimentary storage upgrade when you moved to iCloud. Your upgrade expires on September 30, 2013.
When it expires, your iCloud storage will be automatically adjusted to the free 5 GB plan. Note that you are currently using 8.04 GB of storage. If you exceed your storage plan on September 30, 2013, iCloud Backup, Documents in the Cloud, and iCloud Mail will temporarily stop working.
To continue using these iCloud features without interruption, reduce the amount of iCloud storage you are using or purchase a storage plan by
September 30, 2013.
For more information, see this article.
