"Notwithstanding the foregoing, in the event Landlord requires Tenant to carry any forms of insurance or amounts other than as specified in Article 13 and Sections 15.1 (a), (b), (c) and (d) above and, as a result of such additional required coverage the aggregate cost to Tenant of the insurance required hereunder increases by more than $2,500 in any given year, the Tenant shall be entitled to a re" . . . .