I did some digging, didn't find anything substantive.
Looking at the Linux setup and doing a lot of Linux research, I reset my domain to 'local' and shortened my hostname to 'RPi4' (got tired of typing 'raspberryp4'.
When I restarted this afternoon the program started as expected.
I dislike intermittent issues, but this Pi computer should stay running 24/7.
Just thought I should update you since you have given advice on resolving the issue. Even though it appears to have resolved it itself. (pun intended)
Wayne