The service reps are used to CELs, so you should get used to it too!
I've had some CELs and brought it to Circle Porsche in Long Beach, and also Newport Porsche. In my case it was always manageable issues with the MAF or fuel/air mixture control.
If the CEL is on and stays on, then from my experience I see you can bring it in within 3 or 4 days or so. On one occasion, for me, the CEL turned itself off after two days. The dealer said that the system is capable of readjusting the mixture and correcting itself.
If the CEL is blinking, pull over immediately and get it towed to the dealer.
Also I was disappointed with the quality of my service at Newport Porsche. They were very friendly, but missed some work. I went to them 2 times for a CEL. The second time it came on they checked it out again. Also as I left I remembered "oh yeah can you replace the burnt out headlight bulb?" and the service rep wrote that in pen on the work order. Later I picked up the car, drove home, and that night found that the headlight was not replaced. I went back to them the next day and learned that 1) they always do a quality check from a "very experienced" technician who is "very good" and who "should have seen the headlight problem" and 2) they are not allowed to write notes in pen on the work order - it must be typed in to the system. It just alarmed me, how can they miss a burnt headlight? It is on their quality checklist of things to look for, but they do not refer to the checklist, and they don't seem to remember whats on it either. What else did they miss?
So now I go to Circle Porsche who is also friendly, and are 20% cheaper than Newport. I have found that Circle does miss some items, and I have gone back to them more than twice to repair something. Also they scratched my rear window, but replaced it for free. Basically I consider it the same level of quality but more convenient to my work and much better price.
Good luck Rondog! I hope your CEL is minor.