I am running most of the Picker suite (extended, blueprinter, belt tools, inventory tools, pipe tools) and have isolated this issue to blueprinter.

With blueprinter disabled, shift+mousewheel up correctly scrolls to the next recipe in a book, and shift+mousewheel down correctly scrolls to the previous recipe.

With blueprinter enabled, shift+mousewheel down works as intended. Shift+mousewheel up always resets the book to the first recipe, and does not scroll to the next recipe.

I have scoured all the keybinds and mod settings, and haven't been able to find any settings that would cause this behavior. Did I miss something, or is it a bug?

I can't reproduce this behaviour. If you have a save game available I can try and reproduce that way

Well, after updating to the latest version, the issue now seems to have gone away. Very strange. Either way, thanks!