TechTool Pro is up to 9.6.2 but it's a **** upgrade because its ability to repair disk damage hasn't improved one bit. As far as I can tell all they did was put a GUI on fsck.
Look up the error 'fsroot tree is invalid APFS.' The only fix that is documented to work is to backup the drive, reformat the drive, restore. No possibility to fix in place. Tried TechTool on it, it gave the same error as fsck/Disk Utility then politely stopped everything and went back to the previous window like it was trying to pretend nothing happened.
It's like having the door handle to your barn break, then the contractor says 'whoops **** we have to tear down the barn and rebuild it around a new door handle' totally ****ing ridiculous.
Pretty sure once Alsoft gets APFS figured out, that'll be something that won't be necessary.
Encrypted APFS drives are also miserably slow, at least half as slow as HFS+.