By-Law Breach in Construction

We have a 6 lot block. One lot has a double entitlement due to owning a unit (1 of 6) and a basement. The owner wants to build a 2 bedroom unit on this vacant basement space. After negotiations with the other owners, an agreement was reached and the lot will be split into 2 lots, one an existing 3 bedroom unit, the other a new 2 bedroom unit as defined under Works in the special by-law created for this construction. Upon completion of the works, the unit has been advertised for lease as a 3 bedroom unit. The owner, when asked, has confirmed the unit is a 2 bedroom unit. An inspection of the property (when open for inspection) would indicate that there are in fact 3 bedrooms. Is this a breach of the By-Law? What remedies are available for this breach?