It may mean that the WCS and T & C planes cannot be achieved using your post p.
WCS is set as per your setup being used. T/C planes are how the planes are then presented to the spindle axis.
So...
If you have a 3 axis machine, then the WCS=T=C
If you have additional axes, then the WCS is how you set the part in the machine, with the origin set the same. Any planes you create, should be presented to the spindle in the same manner, with a corresponding origin being set for that view.
Simplest thing you could have done was set WCS to be the FRONT, set T&C planes to the same as the WCS, then program your features.
The "TOP" plane is what you have set as the WCS