3 day minimum auto backup period

Is the 3 day minimum on the automatic backup in settings a feature of the free version only, in that once a day backup is available on the paid version?
If so, is there available a detailed list of all software changes on the paid version?
Or, are there no software changes for going to pro, just support changes?
I don’t understand why 3 days is stipulated, instead of daily as an option as well.

It is the same in all versions. Just change it to 1 day if that is what you want.

I had been trying to adjust the backup frequency, not realizing that I had to first check the box for backups, before I would see any optional frequencies. Thanks.