Helped my friend get started with CFW last week, and sent him out with his Switch doing a full nand backup with full verification on Hekate. Earlier today he tried to restore the backup on his own since Smash is coming tomorrow and it crashed on restore around 15% in. I went and tried to sort him out but his SYSTEM and USER partitions were corrupt to all hell. SYSTEM has a bunch of corrupted files in that can't be deleted and are reporting being upwards of 300 GB. USER partition won't even load in HacDiskMount as it says the BIS keys are invalid even though we know they are valid (the BIS keys work on every other partition fine). Went through the ChoiDujour process to try and get him fixed up but the Switch won't boot with the corrupted USER partition. It boots past both boot logos and then gives error 2002-4686 (invalid FAT format for BIS User partition). Does anyone have any advice for us? We do have his PRODINFO and it seems to be intact.