Uh oh. A GE9X has to go back to GE for rework. Probably the second engine that hasn’t been installed yet
It is interesting they need to send it back.
Either there are some test instrument or probe missing or it is a rework that absolutely needs to be done at the factory.
If it was a minor stuff it could have been done in Seattle.
If indeed there is a rework then there could be extra delay because it is possible each flight test engine is equipped with specific instruments for the specific flight test that will be performed by a specific flight test article.
I mean the engines can not be easily swapped around.