I'm working on preparing some text for translation into Spanish and have come across this construction, which sounds perfectly fine to me, but I've been unable to find any definition or description for it in the OED. One of the sentences in question is the following:
In performing a book-to-tax reconciliation, you must identify those items of income and deduction which differ from book to tax.
I'm trying to figure out what the appropriate meaning of in would be here (my intuition says that it's roughly synonymous with when or while.) It is covered in Wiktionary (under "used to indicate limit, qualification, condition, or circumstance") but in their examples in seems to carry more of a sense of by, and I don't think that sense applies to the above.
Does anyone know what this is called and have a source where it's precisely defined?