This 12 hour baggage rule was quoted to me recently when I was actually trying to invoke the 24 hour connection allowance at international gateway cities. To wit:
I'd already had a stopover at HKG on an FAI-SFO-HKG-BNE-HKG-SFO-FAI itinerary (one free stopover allowed in addition to destination) and was now returning on the HKG to SFO leg, arriving 11:30am. I wanted to overnight at SFO and catch an 8:00am flight north to SEA the next day. 21 1/2 hours in San Francisco. So far as I know, legal from past international connections without being considered a stopover. The agent quoted me the 12 hour baggage rule and said no can do.
Baggage?! I don got no steenking baggage!!! I just want to connect within 24 hours at SFO. Missy or anyone got any thoughts on this scenario?