How do I backup my custom amp settings?

I just updated the app and downloaded the new amp models, then noticed that the "custom" category was gone along with all my saved amp settings. They suggested I restore from my recent iCloud backup, so I did; but my old sounds did not show up, and all my saved songs disappeared, too! Those are backed up in iTunes, so I have some hope of recovering them.

So I am wondering if anyone knows of a way to backup the custom amps? Where does that date live, since it seems it did not come back when I restored my iPad from an iCloud backup.

Very disappointed in Apple. Beware of this issue before you update, and if it has happened to you, please report it to Apple so that they fix it!