Wow. Somebody's actually reading my reviews :) And, even better, reading the stories.

I'm guessing the "stationery" misspelling is a typo. You should email them and point it out so they can correct it.

The structure of the story (setting up a mystery of some sort which is then explained at the end) is fairly common in SF (and mysteries, obviously). Which means, I'm sure, that literary theorists have assigned some sort of names to the various parts, but I'm afraid I don't know what they are. I would probably just use "setup" and "conclusion" (or "denoument" if I'm feeling pretentious).