I'm almost 100% certain it's Expedia giving you the run around on this one.

I had a trip earlier this year that was booked directly through OZ where my ICN-ORD leg had a change in departure time. As I was originally connecting directly from my SYD-ICN flight, the schedule change meant I'd have to leave the next day. I wasn't aware of this change, but OZ proactively called to make necessary changes. On the same trip, I had some UA flights booked through Expedia, one of which got cancelled. Without any consultation, or even notification, I got moved to a later flight that was an all-economy cabin flight when my original booking was in domestic first. It took 4 relatively long calls to Expedia to get it sorted out to my satisfaction.