Can someone enlighten me on what logic is going on behind the scenes?

If you search SFO-DEN for 12/24:
- 5:15am departure has H9, Q9, V9
- 6:00am departure has H9, Q9, V5
- 2:30pm departure has H9, Q9, V5.

The only DEN-YYC flight on 12/24 is at 7:03pm and has Q9, V6, W2.

As expected, searching SFO-YYC has V9 for the 5:15am option (10+ hr layover!), V5 for the 6:00am option (9.5 hour layover). However, for the 2:30pm option, it shows U9, H1, and prices at close to $567 rather than $368 despite both component segments having much better availability. Is UA purposely using married segment logic to make shorter connections book into a higher fare bucket and more expensive?