(a) A Reserve Bank as fiscal agent of the United States acting on behalf of the Postal Service may apply the book-entry procedure provided for in this part to any Postal Service securities which have been or are hereafter deposited for any purpose in accounts with it in its individual capacity under terms and conditions which indicate that the Reserve Bank will continue to maintain such deposit accounts in its individual capacity, notwithstanding application of the book-entry procedure to such securities. This paragraph is applicable, but not limited, to securities deposited:

1. (1) As collateral pledged to a Reserve Bank (in its individual capacity) for advances by it;
2. (2) By a member bank for its sole account;
3. (3) By a member bank held for the account of its customers;
4. (4) In connection with deposits in a member bank of funds of States, municipalities, or other political subdivisions; or,

5. (5) In connection with the performance of an obligation or duty under Federal, State, municipal, or local law, or judgments or decrees of courts.

   The application of the book-entry procedure under this paragraph shall not derogate from or adversely affect the relationships that would otherwise exist between a Reserve Bank in its individual capacity and its depositors concerning any deposits under this paragraph. Whenever the book-entry procedure is applied to such Postal Service securities, the Reserve Bank is authorized to take all action necessary in respect of the book-entry procedure to enable such Reserve Bank in its individual capacity to perform its obligations as depository with respect to such Postal Service securities.