Hi @Andrew_Tobin 
Welcome to the community
I’ll share with you a solution of Backup into an external doc, this is my way but others have found different ways
It’s not the easiest but it works and allows you to have multiple origin doc into one central!
(That should not exceed api size to keep working, so data here should be compressed or exported every once in a while)
Another option could be to configure a “Copy Doc” button to be pressed every tot (i dont know if this actually works)
I’m sure you’ll find a solutions
Have a nice making,
Mario