A. If the energy allocation system has been approved by the Commission, the owner may not render substitute bills, unless the energy allocation system has been tampered with or is out of order.
B. A substitute bill shall be distinctly marked as such.
C. The substitute bill shall be based on consumption for a similar billing period in the affected unit, if available, or if not available the substitute bill shall be an average of the bills rendered to all similarly sized units in the apartment house. If none of the above data is available then the substitute bill shall be based upon a square footage allocation.