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no they want to remain and replace the person under the assignment clause in the agreement
"Not to assign the remainder of the tenancy without the landlord,s formal written permission, not to be unreasonably withheld. Any proposed assignee will have to submit to the usual credit and financial checks, references and interview prior to an assignment. All proper costs of the assignment to be paid by the tenant or the assignee as agreed between them. "
There is 6 months remaining on the tenancy.