I've been putting some distance between myself and The Callback to avoid "read blindness" and have been working on a couple of novels-in-progress and some short works instead. One of those short works reminded me that, while I often have the first paragraph come to me before anything else, sometimes I come at a thing from the middle or the end. They say, and I agree, that the first paragraph is the most important one you'll write because without a good opener, no one's going to see the rest of it except maybe your mom.
Getting the first paragraph first is, I've decided, a great gift. Sure, I might change it or just tweak it a little, but just having it there is comforting. Starting in the middle or at the end finds me overthinking the opening to the point where it begins to impact the rest of the story in a negative way, and I abandon it until some eureka moment shows up, or I can cannibalize bits of it for some other project.
Fortunately, that's not the case for the story in question. While I arrived somewhere in the middle, the beginning came to me quickly, and it's coming along nicely. Would that all of my ideas were so I'd be downright prolific.