The Disabled Parking sign in front of the Buffalo Crazy Wings restaurant shows the person in the wheelchair facing to the left, when it should be facing to the right.
The events in the past take place in 1996, which would make Hayley around 16 in the present.
Roger's 1996 persona of Dr. Ya Ya tries to catch Elián González when the Smiths arrive but the Elián González affair didn't occur until 1999-2000.
Stan and Francine travel back to 1996 where Roger claims to invent ecstasy but ecstasy was first invented in 1912.
1996 (Past) Stan says "like Back to the Future," despite the fact that present day Stan doesn't know what Back to the Future is in the Season 4 episode Delorean Story-An (2009).