When a pilot is cleared for a stop and go, how long does this allow them to be stopped on the runway?
I'd like to know if there is a limit in regulations or at least guidance for this.
The AIM covers this briefly (bolded the important part) but effectively you cant sit there very long:
4−3−22. Option Approach
The “Cleared for the Option” procedure will permit an instructor, flight examiner or pilot the option to make a touch−and−go, low approach, missed approach, stop−and−go, or full stop landing. This procedure can be very beneficial in a training situation in that neither the student pilot nor examinee would know what maneuver would be accomplished. The pilot should make a request for this procedure passing the final approach fix inbound on an instrument approach or entering downwind for a VFR traffic pattern. After ATC approval of the option, the pilot should inform ATC as soon as possible of any delay on the runway during their stop-and-go or full stop landing. The advantages of this procedure as a training aid are that it enables an instructor or examiner to obtain the reaction of a trainee or examinee under changing conditions, the pilot would not have to discontinue an approach in the middle of the procedure due to student error or pilot proficiency requirements, and finally it allows more flexibility and economy in training programs. This procedure will only be used at those locations with an operational control tower and will be subject to ATC approval.
The way I read that is effectively you come to a stop and get going as soon as possible. If you intend on doing anything else you should inform ATC. I take this to be a time limit of, as soon as you stop, get going again.