When exporting Presets, BTT will by default give it a name, such as "Default.bttpreset". The next time you do a backup, it will keep the same name. Although it will warn you that you will overwrite it if you don't change the name, I think a safer and more convenient method would be to have a check box to add the date and time to the name, for example "Default 05 May 2021 2205.bttpreset". The program would remember if the box was selected or not. One could then choose which version to import in the event you discover a problem with your presets. It's less critical for those using Time Machine.
I actually just lost the Presets I had created as I had to send my laptop in for service and I mistakenly thought I had everything covered with iCloud. Fortunately I hadn't created all that many. I've since added my laptop to the online service I use for two other computers, but that still requires you export the Presets to get them backed up, as it only gets done with BTT updates.