Other mistake: In the final scene both at the start when Fletcher is walking on stage and in a shot during "Caravan," just after Andrew mouths FU, when Fletcher puts a hand under his jacket the shot goes forward and then immediately shows the same footage in reverse. (01:27:55 - 01:32:45)
Continuity mistake: Ben Bart passed away earlier in the film but can be seen dancing on stage with the character Gertrude, at a James Brown concert where he is performing "I Got Soul (Super Bad) ". (01:46:00)
Suggested correction: During that sequence, they intercut James in his gold jumpsuit, with long hanging-down hair, and James in a black-and-white checked vest, doing the same song. In the black-and-white vest era, Ben Bart is still alive, so the dancing could have been from that era.
While that does seem to be the case, it should be pointed out that Ben Bart died in 1968, but the song James Brown is singing, "Super Bad", was recorded in 1970.
Factual error: Brian Wilson's panic attack on the airplane takes place circa 1964. However, the interior of the plane had distinctive sculpted doors on the overhead bins, a style first introduced in 1983 on the Boeing 757.
Continuity mistake: In the "Another Brick in the Wall Part III" section of the show, look at the missing section of the wall on the right hand side. The bottom bricks of that section change from being filled in to being empty depending on the shot. (01:02:40 - 01:04:00)
Continuity mistake: Rich is dangling a light bulb above his dad's head. When the camera shifts to a close-up of Rich, the light bulb is higher - almost across from his own face - but back to dangling above his dad's head with the next camera shift. This is independent of Rich's dad telling him to "hold the light steady." (00:06:23)