I have read through some of the Amazon reviews for various versions of this adapter, and the common theme seems to be that the partition table gets rewritten to the SD-Card at power on. Always with exactly one MS-DOS partition populated.

The interesting question then becomes, is the rest of the SD-Card still intact? If so, we could kludge a reasonably simple work-around in Hijack to just ignore the read-in partition table, and instead use either a saved copy or an auto-generated table (partition tables are only 512-bytes long, plus whatever "extended" partitions exist).

I suppose the onboard firmware might be doing something stupid like, "if card isn't something I recognize, then auto-format it at power-on". In which case it's a matter of determining how it "recognizes" the card. Most likely it just looks at the partition table. If that's the case, then we just tell Hijack to offset everything by 1 sector, nothing else required.

If you want to try this, I can provide a suitably hacked kernel, builder image, and car2-software image with that kernel.