APFS Time Machine backups with older backups

[Mr. Dee]

So, I just updated from 10.12 to 10.13; I made a backup before upgrading just in case something goes wrong. What I am worried about is making a new Time Machine backup under 10.13 with my old backups based on 10.12. Will doing this overwrite the old backups; and if so, how I can I avoid it.

 

[Weaselboy]

Will doing this overwrite the old backups; and if so, how I can I avoid it.

It won't overwrite right away, but as the backup disk becomes full, TM will start purging the oldest data and that would likely include your old 10.12 data.

 

[Mr. Dee]

Thank you!