Where a notice under section 122 (notice claiming to exercise right to buy) has been served by the tenant, the landlord shall, unless the notice is withdrawn, serve on the tenant within the period specified in subsection (2)... a written notice either—
admitting his right, or
denying it and stating the reasons why, in the opinion of the landlord, the tenant does not have the right to buy.
The period for serving a notice under this section is four weeks where the requirement of section 119 (qualifying period for the right to buy) is satisfied by a period or periods during which the landlord was the landlord on which the tenant's notice under section 122 was served, and eight weeks in any other case.
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