The pilot of Recess, "The Break In", was originally produced in 1996 as a pitch to Disney to get the show onto television. It was originally created with noticeably different animation and character designs than what would be standard for the rest of the series. After the series was picked up they decided to air this episode as the show's pilot (alongside the episode "The New Kid") but reanimate it with the newer character designs they decided on.
The original pitch version of the pilot with the older designs and animation has been released to the public. However, clips of it do appear on a "Sneak Peek" ABC Saturday Mornings promo viewable on 1997 VHS releases of 101 Dalmatians (1996) and "Doug's Birthday Blues" (and possibly on station IDs for certain ABC stations). Additionally, a piece of concept art for Vince's design as used in the pilot can be seen on "The Top Ten Secrets of Disney's Recess", a featurette included on the Recess: School's Out! DVD release.
Sneak peek at 101 Dalmatians The Series and Recess (early 1997)
The aforementioned sneak peek video, containing clips from the original pilot.
Concept art of Vince's earlier design used in the pilot, taken from "The Top Ten Secrets of Disney's Recess".