Originally Posted by
jkg2005
Agree with others, most likely explanation is someone bought a ticket while you were searching. Dynamic pricing applies to award tickets too, and an open jaw/return should not price differently from two one ways.
On your second question, these are all UA metal flights so can be booked with pooled miles. It takes a couple of days to set up a pool and move miles over. But like I said, I don't think the issue is not being able to book as one itinerary. Your original strategy was sound, and in fact preferred.
Try clearing cookies / using a different browser PC... might be ticket was purchased (using miles, or cash - either way inventory reduced). OR United shenanigans. I've had different prices/awards from different browsers & PC's...
And I've had one ways quoted as (the combination of two one ways) less than a round trip, the same as a round trip, and more than a round trip. I've even had a one way price out as more than the round trip...