At any time before 1st April 1994 or the expiry of 3 years beginning with the relevant date (within the meaning of sections 46 and 47), whichever is the earlier, an application for the registration of a rent for a dwelling-house may be made to the rent officer by the landlord or the tenant, or jointly by the landlord and the tenant, under a regulated tenancy of the dwelling-house for the purpose of taking into account sums payable by the tenant to the landlord in respect of council tax.

Where an application is made under subsection (2) above, the rent officer shall determine the amount by which the registered rent might reasonably be increased to take account of sums payable by the tenant to the landlord in respect of council tax.

The amount of any rent registered under this section shall be the total of the sums payable in respect of the previously registered rent and the amount determined under subsection (4) above.

In any case where a rent officer has before him for determination applications under this section and section 46 above, he shall not make a determination in the application under this section until he has made a determination under the said section 46.

No more than one application in respect of any tenancy may be made under this section.