New Time Machine Backup after Installing El Capitan?

[gpspad]

I have a time machine that I back up to once a day. I installed El Captain, should I delete the old backups and start a new one from scratch?

 

[keysofanxiety]

I have a time machine that I back up to once a day. I installed El Captain, should I delete the old backups and start a new one from scratch?

Nope, no need to. IMHO it's probably better to keep the older backups, as that means you can restore to Yosemite if there's some app-crippling compatibility issue that you encounter in El Cap.