After following section 3.3.2a of this guide to enlarging the root partition in order to be able to install the latest Sailfish update (126.96.36.199 -> 188.8.131.52), my Jolla Tablet booted up fine, and I was able to install the software update. When the tablet rebooted after updating, I entered my lock code, but it claimed the code was incorrect. I entered the code two more times to make sure I hadn’t made any typos, but it kept saying the code was incorrect. I presume something must have happened to the file containing the code whilst resizing the partitions.
I then rebooted to recovery mode and tried to access the shell, which also asked for my lock code, and also said the code I entered was incorrect twice in a row.
I then rebooted back to the UI, which told me the device is now permanently locked - even though I had only used up 5 out of the 10 attempts I set as the limit.
Strangely, rebooting back into recovery mode always seems to give me five attempts to unlock, even though the UI says I have no attempts left.
Apparently, performing a factory reset is also locked behind the device lock code, which still isn’t working, so now I wonder: how can I get this device to work again?