No Kevin or Duarte versions were produced for unknown reason.
After this episode, Blue will no longer hop across the credit slides until Patience.
This was the first Season 4 episode animated by David B. Levy's team. When this happens, there's usually a repetitive credit sequence during this season. Mr. Salt & Mrs. Pepper usually appear mirrored, around the Executive Producers credit slides. Two of Tickety's actions are chosen from, except for the one where she rings her bells like on Making Changes and Blue's Book Nook, usually appearing around the Storyboard credit slide. Shovel & Pail are usually in their proper position, appearing around the Animators credit slide, and Mailbox is always mirrored, usually appearing around the Studio Crew credit slides. The last three characters listed are on the opposite side for Dale Clowdis's episodes, except Imagine Nation for Mailbox, and Bugs! for Shovel & Pail. There have been some minor exceptions with David's episodes, like in this episode, Tickety appears before Mr. Salt & Mrs. Pepper, and Blue comes back after. More exceptions will be pointed out throughout the season.
In the letter, when the kids find toilet paper rolls as the instruments, they play "Mary Had a Little Lamb" before it ends.