The first beta macOS High Sierra for the iMac Apple has introduced support for his new APFS file system for media Fusion Drive.

However, it disappeared in subsequent builds that although the future is possible to return to support APFS Fusion Drive, in the final version macOS High-Sierra it is not. The company has confirmed it.

RTM-version macOS High Sierra was released earlier this month, and its public release is expected on Monday, September 25th. Apple has posted instructions in advance to help the owners of iMac APFS convert back to HFS + format. It can hardly be called simple: during the rollback, users have to create a restore point, record media, and then format the drive and reinstall the High Sierra.

It is curious that according to APFS instructions will not be supported "in the initial release macOS High Sierra». Perhaps in the future, this will change - but when and whether the change is unknown.

Instructions for returning to HFS + can be found here .