So I can just update my Kindle and then reapply the kindlet JB?
EDIT:
Just did it, everything worked great! ^^
1) Updated KindleTouch from 5.3.7 to 5.3.7.1 (.bin file, OTA wasn't showing any update)
2) It automatically did the JB after the update
3) Kindlet JB was broken, so I reinstalled MKK (it was also a new version, so took the chance to update it)
3b) KUAL was working, but I had an old version so I updated it too
4) Screensaver hack wasn't working, so I just reinstalled (actually, new version here too!) python + linkss and after the reboot everything was working great!