Man, I looked for that setting but didn't see it - thanks for that!
Now, I have to turn off the wifi and restart the app, cos by the time I've opened it and selected no autoupdates... it's already updated
I've got 2.922. It has that bug where it doesn't write the .mobi files in a separate folder, but lumps them into a single file. You can "show package contents" to get at it though...
Sigh.