Saving players' bluprints trough wipes

Hello!
After a recent server reset and reload by my hosting provider i noticed that blueprint memory was cleared.
It's kind of sad and very disappointing. How would i manually make a backup of all users' studied blueprints info?
And is there any server command to save/clear those "memories"?

 

Nope, nothing to get back.

Blueprints saves in persistense.

 

So i have to save the persistence folder?

 

Try it...
But my hosting don't deleting it.