All of my data in nodes that had custom field permissions disappeared. I don't know what combination of factors caused this, but I've tried it multiple times with old backup data. Every single field except for title is empty (I assume because the new field permissions changes it how it writes to tables and the old tables got erased). If someone can help me quickly to get back in working shape, I'd appreciate it. But I'm posting to warn everyone to test this carefully before deployment.