Hochstetter tells Schultz to go back to camp and change into civilian clothes. Shortly later, Schultz is seen in civilian clothes at the front door of the Baroness's house. There was not enough time for him to go back to camp, change, and come back in civvies. This would have taken maybe an hour or more. Update: Since Hogan could walk to the Baroness' house, it must be close to the camp. If Schultz drove back to camp and returned the same way, the whole process could have taken less than half an hour. At the time Schultz knocked on the door, Sears was well along in eating the food that the Baroness prepared. Hogan also refers to getting back to camp, as they lock up at 11:00.
When Captain Sears meets Hogan he tells him he has the plans to a fictitious Operation Anvil. There actually was an Operation Anvil, the planned Allied invasion of southern France. When the invasion was delayed until the following year, the name of the operation was changed to Dragoon.
This is another of many appearances with Sergeant Schultz wearing a uniform that the costume department incorrectly placed the Luftwaffe eagle and swastika backwards on his jacket. It is quite evident in a closeup when Major Hochstetter instructs Sergeant Schultz to dress in civilian clothes to help capture the Englishman.
When Carter and LeBeau go out to signal the plane, you can see the entire camera crew reflected upside down in the reflector of LeBeau's flashlight.
The pun with the gestapo officer at his HQ wouldn't work without a mixed language. The assumption is that the characters are speaking German but the audience hears English. If the officer said the cell was nine, in German he would be saying neun which would not sound like nein to Carter.
When Carter and Newkirk dress as Gestapo men and bring LeBeau to Gestapo headquarters, and officer behind the desk asks Carter for his name, and he just says 'Fritz'. They should have been prepared with phony names and identifications if asked.
Hogan is seen at a party in his Class A dress uniform. Where would a prisoner of war get a Class A uniform?