(a) Upon written request by private counsel, the State Comptroller, in his discretion, may authorize the payment, in appropriate circumstances, of fees for services in a particular case in amounts higher than those set forth in the fee schedule. A request for higher fees must set forth the circumstances justifying the request and shall include a list of the partners, associates and paralegals assigned to provide the services, together with their normal rates. In determining the appropriateness of authorizing higher fees, the State Comptroller shall consider, but not be limited to, the following factors:

(b) The State Comptroller shall approve or disapprove the request for higher fees and advise private counsel of his decision in writing. A copy of the decision shall be transmitted by the State Comptroller to the Attorney General.

(c) Except as provided in subdivision (d) of this section, any fees over and above those set forth in the fee schedule which have been approved by the State Comptroller shall apply only to services rendered subsequent to such approval.

(d) The State Comptroller may approve fees over and above those set forth in the fee schedule for services rendered prior to such approval when exigencies of time and scheduling in connection with the case under consideration effectively preclude a timely request for higher fees.