Hey @RichieRich1891, thanks for posting on our Community and happy Monday!
I can confirm that this the only option is for Backups to happen every 15 minutes, once a day or a week and on a custom schedule at this time.
That said, thanks for taking the time to share your thoughts on this and feel free to take a look at this idea too as it kind of echoes your request.
Let me know if you have anything else to add, Richard.