[NiLuJe]

Yeah, this will break UYK [regardless of the actual issue you encountered being an outdated hotfix package, which is perfectly normal when running a hotfix built before the release of a FW version] (i.e., an initial jailbreak), but will (probably) *NOT* affect MRPI (i.e., an update, for which, I have to repeat this every single time: you don't need to do *anything* about except reboot. *twice*. Reinstalling the hotfix does nothing for you except doing the same job as the first reboot and tripping the second one by virtue of being an update. It is only actually necessary when there are code changes required (which will *now* be the case, I guess xD)).

I haven't looked into it, but I assume it works like any of the other squashfs images in there, so it's a bit of a bitch to deal with (it's a read-only fs image inside a ro fs, (with none of the tools required to build one shipped, IIRC) ;D).

The usual recommendation still apply: don't <expletive> ever update a <expletive> jailbroken Kindle, <expletive>!