DO NOT attempt to do this on a regular basis. I did the SEA-ATL commute (offline, no CASS) for less than one year, and four of them turned into 2 day affairs with overnight stays in the terminals of Denver, Portland, LA, and Reagan. After a whopping one day at home I have to do it all over again. YMMV depending if you have CASS access or not. Trust me - it's no way to live.