Other mistake: The scenery in the "I Love Lucy" on-stage scenes shows the Ricardos' apartment with a living room window. That was the apartment they moved into after Little Ricky was born. Before that, they lived in an apartment with no (visible) window in the living room.
Continuity mistake: In the opening scenes while lost on her way to Sandringham, Diana drives a Porsche 911 with licence plate G580SGT. Later when she stops by the scarecrow the same car's plate has changed to J548LRP, it remains so for the rest of the movie. J548LRP was an actual plate used on a Mercedes SL500 that Princess Diana once owned.
Factual error: The telephone for the phone bank doesn't have a phone jack cord connected into the back of the telephone. (01:15:14)
Factual error: After Mohamedou's torture scenes, the CO of GITMO holds up a letter from the Dep. Of Defense in Mo's face, stating that his mother had been detained. In the bottom left corner of the letter, it is written as "Department of Defence", which is the UK spelling. (01:41:27)
Continuity mistake: Venus' starts off with a burger in her left hand which immediately changes to a watermelon segment, while a cookie has now appeared in her right. She puts the watermelon down only for it to reappear in her left hand when the camera changes angle. The cookie has now disappeared. The camera switches again to show that the watermelon is no longer in her left whilst the cookie has returned to her right... which is swiftly replaced by her half-eaten burger. (01:07:00)
Character mistake: Zack's birthday cake appears to have his name misspelled as "Zach." (00:29:24)
Other mistake: It isn't clear if the poster of the Solar System outside the school was cut off on the right, showing half of Neptune, or if the ninth planet at the time (Pluto) was accidentally omitted. IF the poster was supposed to be complete, its exclusion of Pluto would be an error for the time period (1969) because Pluto was not downgraded to a "dwarf planet" until 2006. Perhaps, only half of Neptune was shown in order to not have to address the changed status of Pluto, making this a deliberate mistake. (00:32:36)
Suggested correction: Neptune isn't cut off, it shows as a complete circle on the "poster" (looks more like a board).
Factual error: Sassoon's Military Cross medal is shown ending up thrown in the Mersey and sinking. In his own words from "Memoirs of an Infantry Officer", published in 1930 - "I ripped the MC ribbon off my tunic and threw it into the mouth of the Mersey. Weighted with significance though this action was, it would have felt more conclusive had the ribbons been heavier. As it was, the poor little thing fell weakly on the water and floated away as though aware of its own futility."
Continuity mistake: When Hagmaier is in the Florida State Prison room waiting for Bundy, his hair changes. Initially, his short bangs are straight across the middle of his forehead. When Bundy sits down, Hagmaier's bangs and top of head are "fluffier" (perhaps blown dry) and combed to the side. (00:11:05)