TFA version 12.1.2.8.4 and later versions do not start listening on default port 5000

During upgrades from TFA version 12.1.2.7.0 to version 12.1.2.8.4, not consistently, but on occasion, the upgraded version of TFA will start and listen for connections on a port other than port 5000.  When this happens the only way I've figured so far to fix it is completely uninstall TFA and then install the new version fresh.  At that point it is always running and listening on port 5000 and other remote TFA processes are able to communicate with it.   I am wondering how the TFA upgrade is picking a port to listen other than port 5000, and if there is