Factual error: In the third scene, when Doug stops Jack for speeding, both vehicles in the scene have North Carolina state safety inspection stickers in the lower driver side windshields, as opposed to a Massachusetts inspection sticker (which would be on the passenger side).
Factual error: When Jack is carrying Jen out of Pacey's restaurant, she bends her head down. You can see that her now very long, curly hair is real and has a natural part. But this episode was in reality filmed right after the preceding episodes in Season 6, not 5 years later. And in the later episodes of Season 6 Jen had dramatically shorter hair. Although in the context of being 5 years later Jen's much longer hair makes factual sense, in reality it isn't possible that she could have grown her hair out that quickly between the Finale and the episodes filmed before it. So how did she? The shorter hair didn't appear to be a wig.
Factual error: When Harley talks Joey into calling Eddy's parent's home in Worcester, Joey picks up the old dorm phone that has a handset cord attached. This doesn't make sense, because since Joey is calling long-distance to Worcester she would be more likely to use her cell phone which probably has a pre-paid plan. The old black phones are standard land lines, that come in the dorms; but the roommates both have cells and they also have a more modern wall phone.
Factual error: When Joey is talking to the Professor, he mentions that her Birthday is the next day. Dawson also helps Joey celebrate her Birthday early at Midnight that night. Clearly this is some time in early Fall, when the Semester first starts at Worthington; probably August or September. But during the Season 5 Finale, Bessie hands Joey her Passport which has Joey's Birthday listed as May 13, 1983. Also, in previous years of the show, Joey's Birthday was never shown to be in the Fall. She didn't even start learning to drive until later in Season 3.
Factual error: Towards the end of the episode when Joey and Dawson are arguing about their relationship, Joey makes a statement that "Dawson bought the Champagne" referring to their romantic time on the movie set earlier that evening. However, when they were having that drink on the porch of 'Dawson's House' on the movie set; Dawson explained to Joey that the Champagne was from a free gift basket, one of many given to Directors before they start production on a new film. Therefore, Dawson never bought the Champagne, he simply stole it from the gift basket.