Airbase supply priority not supported per manual?

[anglonorman]

SECTION 16.6 Says I can change the supply priority of an airbase by clicking on the airbase then right click to access the unit detail window where I Can change the supply priority. However, I cannot do this as it's greyed out and locked. What am I doing wrong?

[Joel Billings]

The manual is wrong. You need to set the supply priority of the Air Command, as that will determine the supply priority of the airbases where the air command has air groups stationed.