Migration is pain: you can spread it out over days or weeks, or get it over with in a much shorter period. Moving your Time Machine backups also requires great care.
Time Machine
Adds support for local snapshot statistics, Dark Mode, fixes a bug, and is now notarized for your added security.
Detailed comparison of how Time Machine backs up HFS+ and APFS volumes, including its use of local snapshots, with diagrams.
With its 2 TB Fusion Drive well over half full, upgrading my iMac from Sierra to Mojave could so easily have been a nightmare.
If you’ve upgraded to Mojave, there are a couple of odd things you may have noticed in SystHist and T2M2. Help is at hand.
When Time Machine backs up an APFS volume, it works quite differently from the way it did on HFS+. Explored here using log entries from Mojave.
Some Macs start running the Mojave upgrade like it’s molasses or treacle: starting an app takes a minute or more, and other function grind to a halt. Here’s why, and what you should do.
Stories about 32-bit support, APFS and Fusion Drives, widespread app problems, failed updates, Time machine, and privacy protection.
Practical tips for those intending to upgrade early, from checking compatibility, preparing workarounds, to making a copy of the installer.
Don’t pay too much attention to what Apple wants you to hear, but beware of what it omits to mention. Time Machine 2, perhaps?
The Eclectic Light Company 