Hitting 'Run Now' causes it to run for many hours, is it just verifying?

I added about 100gb to my backup folders and wanted to get the backups going over the weekend, when I don’t have Dup running. Instead of uploading the 100gb it starts at my 2tb and counts down. Now I understand it isn’t reuploading all 2tb again, I know that, but is it verifying what is uploaded and then uploading my 100gb?

And if this is the case then why did it get about 1TB in and then start uploading slowly - as in it appears to be uploading now as it has gone from 980GB to 946GB at 1MB/s in 12 hours. Why did it slow down midway? Wouldn’t my upload be at the end?

Not necessarily. It checks all selected files on your disk and your added data could be anywhere in the list of files to check.

But with that being said it should be the same speed as if it was just checking the 2TB files and then uploading the 100GB.