Continuity mistake: When we see Harry on the laptop, he runs off and the laptop switches from on to off.
Switcharoo - S9-E5
Continuity mistake: Emma brings Neville a plate with a sandwich, cut in half, while he is in the laundry room. Neville picks up the half of the sandwich closest to him, looks at it, and puts it back on the plate. He then picks up the half of the sandwich farthest from him, holds it for a brief minute, then puts it back on the plate. Only, the half farthest from him is already on the plate when he puts the one he's holding back. You need to look closely as this one was tough to catch. (00:33:20 - 00:33:45)
Switcharoo - S9-E5
Continuity mistake: Emma brings Neville a sandwich in the laundry room. Neville picks up the half closest to him and puts it back down. He then picks up the half farthest from him, holds it for a brief minute. When he puts it back on the plate, the half farthest from him is already there and he puts down the half closest to him. This was a tough one and I had to watch a few times. (00:33:20 - 00:33:45)
Continuity mistake: When JP is talking to Marlon who is having lunch, Marlon's napkin keeps alternating between blowing in the wind and hanging freely.
Continuity mistake: JP and Rosie go from having twins in episode 10.3, to having only a daughter in 10.8.
Answer: Most likely they had only tropical exotic drinks, he wanted an old fashioned English beer.