The Inbetweeners/WMG

Jay is telling the truth
All of his crazy and obviously false stories about his sexual experiences? All of them, 100% true.
 * So he's a paedo who actually peed in a girls mouth?

Carli's dad will be played by Anthony Head
Neither of her parents have been seen since the show's start, potentially developing for a massive reveal. If she is indeed going to appear in the film, perhaps her dad will as well - played by Emily Head's real dad, Anthony Head.
 * Actually, Carli's mother did appear in the show.
 * Jossed by the movie. However, he does play Will's dad.

Will is descended from the Blackadders.
And Neil is a Baldrick.

The Inbetweeners is set in the same universe as Spaced.

 * Derek had to get out of the comic store business after Bilbo poached Tim back and settle into a real job to support Simon and his brother.