Originally Posted by
dc333
They can check your bag through to UA on two tickets provided the connection meets or exceeds the minimum connection time in sea. It's easy to confirm, try building that itinerary on any OTA like Expedia. If you can find it for sale, it has passed the MCT test.
You don't mention any return, but UA and AA no longer offer to interline bags on multiple tickets when checking in with them. There could be a few alliance based exceptions but that wouldn't apply with your carriers.
I didn't hear UA and AA don't do this anymore. Bummer. AS policy in the past has been to check bags through, even on two separate tickets. But even then, the agent working check in has the power to either allow or deny it. There's a chance you could probably get lucky with a UA agent on the return regardless of policy changes, but no guarantees.