For example, if you allow Backblaze to Continuously backup the original file, then it will notice when you make a small edit on that file and figure it out and transmit the changes so BOTH VERSIONS will be in the backup. If you copy the files and bundle them up first, Backblaze Personal Backup won't work as well, and it is not what it was designed for - you might look into Backblaze B2 for that. For example, Backblaze does not backup TimeMachine backups on Macintosh -> Backblaze works best and is designed to backup the original files in their original location. Technically Backblaze is supposed to work on the ORIGINAL files, not on backups (this is against the Backblaze's program's intent and design). If the 'last modified' date does not change, it will not even look to see if the file contents have changed.
If everything is working correctly, then Backblaze will backup any single file when the 'last modified' date changes.
Disclaimer: I work at Backblaze on the code that uploads large files.
