In “Planning”, replace “If an Imagineer has any Planned Buildings in their Zone, then their bids on Demand Posts are ignored.” with:-

If an Imagineer has any Planned Buildings in their Zone, then they may not post bids on Demand Posts.

For each Planning post which was closed while it had a bid which was being ignored under the previous wording of this sentence, increase the Debt of that post’s Winner (ie. move its value away from zero) by X, where X is the difference between the winning bid and the lowest ignored bid.