I've updated my Kindle but am now selling it. If I reset to factory default, will the updates need to be downloaded again?
Haven't reset my Kindle (Paperwhite 2) for a while, but as far as I remember the updates stayed there, so there was no need to update from scratch.
I guess when you update a Kindle, you just update operating system of the Kindle. And when hard-resetting, you're just wiping all the data and restoring the default settings etc. for that version of a system.