Originally Posted by emcampbe

Define typical. Technically, the SDC rules require the itinerary to be all UA-operated to be eligible for an SDC. No automated tool will allow otherwise, for sure (though I believe I've seen the change flight options when I've completed all partner segments and only UA segments are left). I'm sure there are agents who will allow SDC off of a partner onto UA metal, though I'm guessing that's not going to be the standard answer.