Happy to say that Apple has fixed the bug in 10.15.5 that caused firmlinks to not be connected after being copied by backup programs.
As you may know, this had two symptoms:
The backup looked incomplete, with some folders seemingly empty on the backup drive.
Note that the backup was complete, but because the firmlinks weren't fully connected, you couldn't see the files on the Data Volume without specifically looking for them in /Volumes (which you could access via Go To Folder in Finder).
The backup would boot about 2/3 of the way, and then shut down.
Both of these symptoms were caused by the same symptom. We provided a workaround on request for users who needed it, and while convenience was impacted, your data was never in danger.
Fortunately, it's fixed in 10.15.6, and a normal Smart Update will repair your backups and all will be back to normal.
Until Big Sur, of course...where the "adventure" continues. More on that when I have something good to say.
