2007 R56 Hatchback; 127,000 miles

Few weeks ago CEL came on. Pulled the codes, need to replace my activated charcoal filter on the fuel tank and the fuel vapor detection pump attached to it. Tried to do it myself; cannot get the two screws holding the charcoal filter off -=- they are attached to plastic nuts, just turn and turn.

Taking the car to the dealer Thursday -- a 2 hour trip -- and let them figure it out, service advisors says no problem.

Now, the CEL has gone off. Does this mean:
(1) error has cleared, no problem, cancel with the dealer and forget about it, or,
(2) error still there, CEL will return after a few miles?

I drove it today, CEL was not on when I started the car, drove about 30 miles, CEL did not return.

Thanks.