Originally Posted by
soccerref750
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Maybe someone can explain this difference. Also, I'm curious if I did book the new one-way (though I don't plan to), would I be allowed to merge the itineraries, or would it invalidate my original ticket when I didn't take the outbound flight?
I think you are right about the B fare effecting the new fare, the lower fares are probably not available due to advance purchase requirements.
You will not be able to merge/replace a new segment into your present itin. If you do not flight your scheduled segment, the rest of your itin will be cancelled.
This really points out the value of SDC.