Why Deck 12 mid-ship cabins have a smell issue on embarkation day

Worked culinary on Celebration. Deck 12 mid-ship on the port side is directly above the main galley ventilation exhaust. On embarkation days when we're running all stations simultaneously prepping for the first dinner, those cabins get a food smell — usually bread and industrial cleaning products — for about 3-4 hours from 11am to 2pm. After that it's completely fine for the rest of the sailing. I've seen guests request room changes on embarkation afternoon thinking something is wrong with the room. Nothing is wrong. It just smells like a bakery for a few hours. If you're checking in early it's a thing to know.