On 2/16 the MSP-EWR segment is flown as CO ExpressJet, the next day it is Shuttle America/United Express...does this mean I can't SDC onto the 2/17 flight because it's now operated by UA? Also, what happens when one segment is CO metal and one is UA metal, if I push back the CO metal flight, I'd have to be on a different UA metal flight, can I still make the SDC change? This merger stuff is starting to get really complicated and confusing.