Originally Posted by
christep
You can change your seat assignments on most OW carriers in business if you call the airline directly (it would probably help if you can get each airline's underlying PNR). It's only BA that refuses to do this for anyone except full fare J.
Actually BA allows BA Silver to preselect seats per the
seating policy page.
I would be calling back re those Domestic US flights ASAP - you don't want to be in whY if you have the choice