Glad it all worked out in the end. Sounds like it was a simply case of WGA being sold out for the routing, forcing you to AT fares. And a WGA came back either due to a cancellation or opening up of the bucket.

But there are many routes where NO WGA, AT or BS bookings exist as a 1 ticket itinerary forcing one to try the 2 one way routings. And I always check a connection separately for kicks and have saved $$ or points doing so.