Ok, that looks like a nice tool. Thanks!
Was just going to suggest rclone as well, but for its easily toggle-able bandwidth limiter. I have slow rural internet; restic backs up locally every night, rclone then syncs it offsite. A systemd timer throttles it during walking hours and lets all 6 mbps rip overnight or when out of town.
There are also throttle options for bandwidth. I use that combined with Node-Red and a smart plug on my monitors, if monitor power draw exceeds a threshold then the upload throttle is changed via the rclone API.