Ask HN: Backup service to back up all files newer than date X?

Before Comcast introduced data caps there wouldn't be a need for doing this but now it seems best to back up only files newer than date X.

Start by making a copy of the current files onto an external hard drive, unplugging it, and putting the backup in a safe place. Instead of trying to deal with bringing the backup home, syncing, taking it away, etc. the software should only back up files going forward.

It seemed like rsync did this but looking at the man page there's only reference to updating files that have been modified or don't exist on the backup.

BackBlaze seems awesome because of their restore via hard disk for free (you pay for a 4TB hard drive but you get your payment back if you send the drive in within 30 days; you can get multiple drives if you need to). But they don't offer to back up only files created (or touched or whatever) after X date.

One way to circumvent this is by creating a directory - "new videos" - and backing that up while excluding the "videos" directory from BackBlaze. Or creating a "videos to backup directory" and move files into that incrementally.

I really, really hate that Comcast was able to implement data caps with no consequences because all of the other alternatives were worse. With the "spare" room after Youtube, Netflix and so on at our house it would take over 2 years to back up existing files.