Paging @NiLuJe - the target OTA version for the hotfix seems to be out of date (3887160041 vs 3889290042 for 5.15.1 or 3900690052 for 5.16.1).
This is probably the cause of the issues that people are having here:
https://www.mobileread.com/forums/sh...=345655&page=4
Would it make sense to set the target OTA version to something implausibly high (e.g 9999999999) to avoid the need to bump it every time that Amazon releases a new FW?