based on uniform production rate, VIN xxxx N552638 would have been produced on the 1st production day of December (Monday, 2 Dec) whereas Kelly King's VIN xxxx557961 would have been produced either the 6th or 7th production day of December (9 or 10th), a week later, so if they were really hustling that first week or December, (to make up for the Thanksgiving day they missed?).. maybe Kelly's car was produced a day or so earlier than would have been expected - to put them into the same production week?