First ,best choice is always call service.
They, usually ,don't monitor this forum.
Tony,or one of the folks,will give the correct answer,where we might spend several days making guesses.
You can try opening the door,and dumping some heat.
If it will settle at around 250* at the cooking spot,the butt will handle it.
The butt, acting as a heat sink,could help settle the temp.
I always hate to miss a planned cooking day.