13. For the purposes of this Part “termination date" means—
(a)31st March in the relevant year; or
(b)where the rent officer’s determination replaces a determination made in relation to the same dwelling, the day before the relevant date of the new determination by the rent officer in relation to the same dwelling as defined by paragraph 12; or
(c)the date on which the allowance ceases to be paid in respect of the tenancy,
whichever is the earlier date in the relevant year.