I suspect it's another improvement to .bomb: I have not been able to price LH codeshares on UA metal since about a year ago now. Previously, it would be hard to make the agents to price them, and now the bomb too seems to crash every time I request codeshares. In this regard AA is much more advanced with their online reservations: many many times I could even buy cheap BA tickets within Europe, that even ba.com were pricing much higher.