(a) The period of twelve consecutive months starting on the commencement of availability; and
(b) Each subsequent period of twelve consecutive months until expiry or termination of this contract pursuant to sub-clause 10.1 (expiry); if the time period which ends on the expiry or termination of this contract and which begins with the end of the last period of full twelve consecutive months is less than twelve consecutive months such time period shall nevertheless be deemed to be a contract year for the purposes of this contract.