Lost videos after hard reset question

[sprtfan]

My wife's phone is a Lumia 822. Whenever it tried to download an update it would get an error. We had to do a hard reset to fix it. We did a manual back up for settings and apps and have had automatic back up for photos + videos turned on along with txt message back up. After the hard reset all of the videos and pictures were gone. Is the only way to get them back to move them down from onedrive? Is there any other way to get them? My wife says that some are missing from onedrive. I'm guessing that we may not have turned automatic back up on for videos until after she already had a few. Once back up is turned on for videos, does it move all videos to onedrive or just from that point forward? Thanks