Aircraft on order... Red?

[MattDell]

What does it mean if an aircraft you have on order is highlighted in red?  I know green means it's been delivered.  Yellow means it will be delivered in 2 weeks.  I don't see anything about red in the manual and I've never seen red before on an aircraft order.

[slither360]

In the production slots view, if you click on a specific order, that order gets highlighted in red on your "aircraft on order" screen.

[MattDell]

Ah!  That also explains why it went away after I posted.