When I place a fishing rod into the enchanting table, only 1 or 2 options come up for enchanting. Neither of them work even when I place the lapis required and have the experience to pay for the enchant. When I remove the fishing rod from the enchanting table and place another enchantable item, THAT item will only have the same 1 or 2 options the fishing rod had, are typically the same enchant costing 2 different amounts, and will have to be purchased to get the enchanting table functioning properly again. Enchanting table has 22 bookshelves in range and functions properly otherwise.
I'm going to say I've seen this too, at least the limiting to 2 choices after a fishing rod is enchanted.
you only need 15 bookcases btw.