With the current situation in the South China Sea, the Chinese government are unlikely to approve any solution Boeing come up with, particularly as the aircraft already in China aren't needed anyway due to the reduction in air traffic.
A downturn of 1 - 2 years would suit COMAC very well as it gives them time to catch up with the C919 program and be ready once airlines start buying again, possibly grabbing a few orders which would have gone to Boeing because their aircraft wasn't ready earlier.