Okay, interesting. I’m thinking about whether I should. The one shot is setting up the story in many ways. They have a conversation at the end about wanting to do something. The “first chapter” of the spin-off would be them doing the thing they talked about. But I’m also sorta thinking that a later chapter in the spin-off sorta refers to the one shot. In fact it’s sort of a mirror image of the original one shot.
As I opened the long-story with them playing a game in it, I didn’t really explain the origins of it. Thus, nice tidbit to those that read the holiday story. To those that didn’t, well, still get entertained.
I think it largely depends on whether or not referring back to the one-shot chapter would be sufficient to bring readers up to speed. There’s also the question of new readers, who might not have read your Scooby Gang Time story.
When I wrote Dale’s Game, it was “the continuation” to the holiday oneshot I wrote. Basically the oneshot explained where the gaming rig came from, the basics of the friendship, and the first chapter of the new story starts off with the boys using it.