John Larroquette's character on "Stripes" (Captain Stillman) was also sent to the Arctic circle as a punishment.
The maximum age for being called up for service in the Army reserves is 42. Dan turned 40 early in season four. This means that he would be already be 41 and this would be the Armys last year to call him up for duty.
3rd and final appearance of actress Judy Landers. Coincidentally, it is also her different character. She plays "Major Roberta Savage" here. She also played "Dan's Date" in S3E15 and "Vickie Guyer" (the bride) in S1E3.
Based on his insignia Dan is a captain in the army reserve.