Constructing tiles on a natural background should yield dig errand before it

[yvvt0379]

The tile construction on natural background errand should yield a digging of this background errand before this errand.

Edited May 30 by yvvt0379

[Tenedas]

not sure how i feel about this. 

What you say have a lot of sense and is consistent with the behavior of the dry walls.
On the other hand i'd like to keep the natural backwalls for late game and get fomo by breaking them since can't be recreated.

Would give big ups if we could recreate natural backwalls 100%