You need a new lease which you can assign. Failing that, you will have a continuing business tenancy held-over after fixed term expiry and protected by part II of Landlord & Tenant Act 1954 [unless Act's effect was excluded by Court Order before lease completed].
Originally Posted by Nee
Once you assign to your purchasers, you are not liable on lease itself. You might be liable if (but only if) L requires you to guarantee purchasers' liability but even that will end when they assign to someone else.
JEFFREY SHAW, solicitor [and Topic Expert], Nether Edge Law*
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