At 3:09 LeBeau has already gathered up the rope used to hoist the flier into the tree. It rests coiled under LeBeau's arm as he says good night, yet you can clearly see the rope in front of the flier when we cut to him in the reaction shot.
Hogan and his crew want to help London during the Blitz. The Blitz took place mostly in 1940. By the time Hogan and his men become prisoners, the bombing of London had largely ceased.
UPDATE: This is not a goof. From January to May 1944, the Germans conducted Operation Steinbock, nicknamed the "Baby Blitz," which was a series of Luftwaffe (German Air Force) bombing missions against southern England, including London, that killed more than 1500 civilians. In addition, starting in September 1944, more than 1400 unmanned V-2 rockets were launched at Britain, most of them targeting London and killing more than 2750 Londoners.
UPDATE: This is not a goof. From January to May 1944, the Germans conducted Operation Steinbock, nicknamed the "Baby Blitz," which was a series of Luftwaffe (German Air Force) bombing missions against southern England, including London, that killed more than 1500 civilians. In addition, starting in September 1944, more than 1400 unmanned V-2 rockets were launched at Britain, most of them targeting London and killing more than 2750 Londoners.
General von Lintzer's staff car has its steering wheel on the right side. In German vehicles, the steering wheel is on the left side.
At 3:09 LeBeau talks to Billett (the flier) from the ground after he has climbed down from the tree, but in the reaction shot of Billett you can clearly see LeBeau's feet still in the tree behind him.
Right at the start of the introduction, the overhead shot of Klink walking from his office steps over to the prisoners shows elongated shadows from nearby lights (the change in the angle of Klink's shadow as he walks verifies that these are nearby lights). The shadows that Klink and his guards cast when Klink starts walking go from him directly to his right side (perpendicular to the direction he is walking). As he is walking, the shadows change angle, and end up behind him and to his right at about a 45 degree angle. For the shadows to act the way they do, the light source had to move from approximately the corner of Klink's office building to the corner of the barracks building while Klink was walking and the camera was turning. Then, when the camera angle changes to the ground shot, all the shadows now go to Klink's front, indicating the light source is now from behind Klink and his guards.
There are two reflections from production lights on Klink's bald spot. As he moves his head, the light locations move, indicating they are fixed.
It makes no sense that Klink would be 'entertaining' Carter in his office. Given the purpose and sizes of the meals, Klink would serve the meals in his quarters. The only reason the meals were served in his office is because Hogan had to be able to listen in on the conversation, and the office is the only place where the bug is located.