Look closely at the log output from Installer.app or installer; you will see entries regarding the search and final location of the relocated application.

What does the
installer log say?

Did you manually create the
/Applications/FileBot/ folder and then move the
FileBot.app file into that, and then install FileBot again? Because then
BundleIsRelocatable would indeed make sure to update FileBot into the manually created folder path.

Presumably,
BundleIsRelocatable is default behaviour so that users can take the
FileBot.app and move it somewhere and then have updates install into the new manually created folder path. I don't know if it can serve as a work around for the issues described in the OP as well, but according to my understanding, you never moved
FileBot.app and yet macOS decided to create a
/Applications/FileBot/ folder, so that seems to be significantly different.

Notably, the
/usr/local/bin/filebot link is created by the
postinstall script and so even if macOS decides to install the app bundle elsewhere, it should still be linked correctly, unless macOS installer itself doesn't give us the correct installation path, so this is certainly a mysterious one:
Code: Select all
# $2: Full path to the installation destination.
# For example: /Applications
ln -sf "$2/FileBot.app/Contents/MacOS/filebot.sh" "/usr/local/bin/filebot"