The Cancel cube must be used immediately after its auction, or it is removed from the game.
The Cancel cube allows the player to discard a previously-placed Building Permit. The piece is removed from the game along with the Cancel cube. If there are any Building Permits in the same development lot as the removed piece, adjust the development requirement of the row to reflect the value of the removed Building Permit. If there are no Building Permits in a row after the removal of a Building Permit from using the Cancel cube, the development requirement is the original 4 development lots.
A Building Permit that lengthens a row may not be removed if the development requirement would be shorter than the current amount of developed lots.