I am doing a “rclone copy local gdrive:” Over ~400 files (500gb) and it already has the bulk uploaded. I had to resume at some point and not matter what, its stuck at "Checkking: " files, without progressing.
I switched from ACD to GD and it seems using GD rclone utilizes checksuming and not only sizes. The longer checking times was a result of the checksuming. Disabled some flags and voila, working again!