So you set that value copy_eeprom or whatever =True and you get persistence, otherwise it's a fresh eeprom every time? Or to put it another way, setting copy_eeprom means "use the copied eeprom"? Or does it mean "do a copy of this eeprom and we'll load it next time". It must mean the former, but I feel a bit ambiguous.

Perhaps a name without ambiguity? use_saved_data - depending on how this actually work?

I like. I haven't tested this but code looks right. Merging.

... and doc in readme/ command line help if not done.