Welcome to the forum @kmand
I like the @drakar2007 plan also, because you get to choose what’s most important to back up quickly, and because of a quirk where restore can’t be done at all until at least first backup has finished by itself.
Current canary can do a bit better, and has some bugs removed (but not all) around interupted backups.
After interrupted backup, Duplicati wants to start re-uploading everything! explains how topic title wasn’t actually what was happening, and points to what in theory should happen, but some doesn’t work yet…
I’d recommend the conservative plan of small increments that are allowed to finish. Awkward, but safer.