Hello @bcherb2 and welcome to the forum!
How does Duplicati Resume After Interruption? is one of the better explanations I’ve seen on what’s happening.
Interrupted backups due to a reboot is another case of the question. I think there was also a recent forum case which started out worrying but found that things indeed were not restarting from scratch. I can’t find that now…
If you want to see what’s actually being transferred, use About --> Show log --> Live --> Information to see files.