[1.07.01 Steam] Readiness combat modifier wrong

[Kaspar]

The 3rd light armor batallion is at 100 readiness. Despite this, it has a low readiness modifier in the attack planner.
Interestingly, the size of the modifier changes if I select a different hex for this unit to attack.

[zgrssd]

Movement does cost readiness.
30 Readiness for all full 100 AP moved. It is only 10 Readiness/100 AP for Tanks and Vehicles.

Maybe it is calculating off the readiness you would have after spending AP to move into that terrain?
After a sucessfull attack, you always can move into the square, even at 0 AP. Indicating it was paid ahead of time.
And if it is terrain based, it would explain why the value is different for different hexes.