Thanks so much for your reply and info.
To answer your question; Yes, this happened all at once. Smelled a faint propane odor while standing next to the cooktop-which had never previosly happened.
In an attempt to logically divide and conquer this, the following day (yesterday);
1) I reopened the cooktops shutoff valve and monitored for leaks=no leaks.
2) fired and ran all the burners repeated times=no high flames/all were normal.
3) shut down the shutoff valve and have not used the cooktop since.
In thinking back. The last to use the cooktop prior to the event was the kids warming up soup earlier in the evening. I was in the kitchen monitoring and there were no issues. A couple of hours later was when we smelled a slight propane odor.
My thoughts are;
Could the Rt. Frt. burner valve they were using not been fully closed? Could this have caused a bit of propane to settle in the right side burner tubes and blast out both right burners upon our initial start up after smelling propane?
Or could the rt frt valve slowly be going bad and need repalacement?
I'm guessing that if the regulator fails, it fails for good rather than intermittently. Therefore I believe the regulator is okay?
Now that everything seems to be back to normal, should we cook on it a few times closely monitoring, then shutting off the propane valve after each use, then see how everything goes after a few uses? Should I replace the rt frt burner valve as a precaution? It seems really odd that both right side valves failed simultaneously.
I'd hate to start throwing parts at this if it isn't needed. (This was an expensive unit and I didn't foresee having issues with it this soon but I guess that's a whole other topic)!