(a) Any landlord may petition the Rent Control Officer to adjust the maximum rent ceiling applicable to his accommodations to compensate for a substantial major capital improvement or structural change as distinguished from repair, replacement, or maintenance.
(b) Any tenant may petition the Rent Control Officer to adjust the maximum rent ceiling applicable to his premises on the ground that unduly high rents are being charged or that the maximum rent ceiling permits the receipt of rent substantially in excess of the prevailing rent for equivalent accommodations.