APFS support for external harddrives?

Hi there!

I understand your concern, however I haven’t had any issues in regards to APFS as opposed to HFS+, at least not yet. I doubt the Time Machine process would transition to a full on cloud service, just due to the fact that Apple already has iCloud, and keeps trying to perfect and excel that service as it is. Time Machine works amazingly as it is, whether it in use by external hard drives or network drives, (I personally prefer a usb drive). In any case, I keep more than one backup on more than one external drive, although I don’t believe worrying about which format each is, is an issue. The only exception is the HFS+ formatted drives I’ve used since Sierra and before. I think after Catalina I started to format as APFS, just to keep up with the times. However, I still have not had any issues pulling data from the older drives, unless the drive started failing on its own.

All of my external drives are APFS formatted; no issues.