Producer milk means milk that the handler has received from producers. The quantity of milk received by a handler from producers shall include any milk of a producer that was not received at any plant but which the handler or an agent of the handler has accepted, measured, sampled, and transferred from the producer's farm tank into a tank truck during the month. Such milk shall be considered as having been received at the pool plant at which other milk from the same farm of that producer is received by the handler during the month, except that in the case of a cooperative association in its capacity as a handler under § 1001.9(d), the milk shall be considered as having been received at a plant in the zone location of the pool plant, or pool plants within the same zone, to which the greatest aggregate quantity of the milk of the cooperative association in such capacity was moved during the current month or the most recent month.