Doing an image-based backup of a data drive, about 1.21TB plus another 438GB. Runs every day in the evening, backing up to cloud storage (Backblaze.) The backup of changes varies; looking at last night's log it backed up 6.5GB which took 40 minutes. But then it says it copied 1.51TB 'inside the cloud', which took over 3 hours, then it deleted 1.52TB. I want to understand why it's doing this. I haven't determined yet what this is adding to the billing for the cloud storage but it's higher than it's ever been since I started using Forever Forward Incremental.
I am having a similar issue with Forever Forward Incremental. In my example it identified 304 KB to backup, uploaded 5.1 MB, and then decided it needs to copy 868.8 GB inside the cloud and timed out after 700 GB and 5.5 hrs because it exceeded the window I gave it.
Forever Forward Incremental (FFI) employs in-cloud copy technology to synthesize full backups directly in the cloud, eliminating the need to upload full backups from your local computer each time. This significantly reduces the time required to create a full backup copy. With FFI, each time a new full backup is created in the cloud, the previous full backup is purged, allowing you to store only one full copy in the storage and thus keep your storage costs low.