NavModifier question

Hello all, I have added nav mesh modifiers to my units in my RTS game. Normally, these modifiers are set to have a class of “None”. When the units stop while in combat, they change to “Obstacle” so other units can move around them and engage.

However, I noticed that while viewing the nav mesh with the “show navigation” command, the nav cell under any moving unit is in turns red. I assume this means it is calculating, but it doesn’t change any of the polygons under the nav mesh like it does if the modifier is set to “Default”. This even occurs when disabling ticking on the nav modifier component.

Does the red nav cell strictly indicate that some heavy calculation is happening, or is there an alternate reason it shows? If so, and I guess, also, is there a more eloquent way to change the navigation properties of pawns during runtime?