The iPhone originals stay in their own folder. If a card needs a brighter version later, we still have the file that arrived, not a flattened leftover.
The clinic's front-desk computer runs Windows. The volunteers who photograph the animals use iPhones. For two weeks in a row, the adoption-board JPGs we thought we had received were actually HEIC files, and the waiting-room PC opened them as blank tiles. We stopped emailing "can you export that again?" and started converting the files in the browser, on the same machine that prints the cards, without sending the photos out of the building. The originals stay in an "as sent" folder. Converted files are named with the kennel ID. We proof the print on the actual cork board, not only on the monitor. Photos that are really a hallway, a shoe, or three animals at once go back to the photographer instead of being forced onto the board.