The market administrator shall establish an account for each handler who is required to make payments to the producer settlement fund or who received payments from the producer settlement fund. After computing the uniform price and each handler's pool debit or credit each month, and at such times as he deems appropriate, the market administrator shall render each handler a statement of his account showing the debit or credit balance, together with all debits or credits entered on such handler's account since the previous statement was rendered; provided, that the handler operating a pool plant receiving milk from a partial pool plant or partial pool unit without producers as defined in section 20.6 of this Part, or from a partial pool plant in the 401 miles or over freight zone, shall be responsible for the debit or credit arising on milk so received and for the payment of the administration assessment pursuant to section 20.85 of this Part on such milk.