Hi All,
I'm trying to price out a mileage run PVD-OAK on a UA S fare, and I'm running into something really strange with the availability. I think it might have to do with the term "married segments" that I've heard around here, and I'm looking for your advice.

Here's the story. I'm using ITA to price out the itinerary PVD-IAD-JFK-LAX-OAK, all on UA/UX metal, booked in fare basis SA14AN. Using the UAL.com 'expert' view, I checked for availability for each segment (individually) in S -- no problem, availability was there.

Now here's the strange thing:

If I do a fake booking for JFK-LAX and then LAX-OAK separately, I see:
JFK-LAX: F9 C9 Y9 B9 M9 E9 U9 H9 Q9 V9 W9 S9 T0 K9
LAX-OAK: Y9 B9 M9 E9 U9 H9 Q9 V9 W9 S9 T9 K9 L8 G4

BUT: If I do a fake booking for the very same flights JFK-OAK-LAX (to get both segs at once), I see this:
JFK-LAX: F9 C9 Y9 B9 M9 E9 U9 H9 Q9 V9 W9 S0 T0 K9
LAX-OAK: Y9 B9 M9 E9 U9 H9 Q9 V9 W9 S0 T0 K9 L0 G0

What's going on with the availability? Why does it change based on whether or not I query the availiabilty with a connection or separately?

It's annoying -- I got this itinerary to price out in S last night and now it won't work, presumably because of what I'm seeing here. Any ideas on how to get around this?