Originally Posted by sbagdon
There is the exception (supposedly) if your layover is between the last flight of the night, and the first flight of the next day. Then the domestic layover can be greater then 4 hours.
Steve B.
There are other exceptions too (e.g. domestic within another country, "next flight out" semantics, etc.), and many of the automatic pricing systems (including us) don't handle a lot of them because they're ill-defined.
That's why I sprinkled the word "generally" liberally through my post
