Breaking out this scope into its own CLIN and associated contract type is a feasible solution. The contract type of T&M would allow for flexibility, but then the Government would need sufficient surveillance to ensure proper billing and clause 52.243-3 would have to be included in the solicitation and resulting contract. The changes clause does allow for flexibility as well, but of course that would be through a change order via a SF 30 and any applicable equitable adjustment for the contractor. 

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