§ 91. Procedure under plan. a. Upon the completion of such plan, but before final adoption thereof, the commission shall hold a public hearing thereon at which citizens shall be entitled to appear and be heard. The commission shall transmit a copy thereof to the board of estimate of the city and to each of the railroad companies which owns, leases or operates any of the railroads included therein with a request for the statement of the views of such board of estimate and such railroad companies thereon. Such board of estimate and each such railroad company may transmit such views and be heard thereon within a period of time to be prescribed by the commission. Thereafter the commission, from time to time, may make such changes in or modifications of such plan as the commission in its discretion may deem to be advisable. The commission shall then formally adopt the plan and call upon each of the railroad companies which owns, leases or operates any of the railroads included therein or whose leasehold, contract or other interests are to be acquired to inform it within a period of time to be fixed by the commission whether it accepts such plan. Any such plan as formally adopted by the commission may provide that the commission, with the approval of the board of estimate, from time to time, shall determine whether and when a sufficient amount of the securities to be adjusted have been deposited under or have otherwise assented to the plan to render it advisable to declare the plan operative, and in such latter event the plan shall not be or become operative until so declared by the commission with the approval of the board of estimate. If the railroad companies or one or more of them do so accept, or if in the judgment of the commission a sufficient number of them so accept as to justify carrying out the plan, and if the board of estimate also approves the plan, and the plan is or is declared operative in accordance with its terms, the board of estimate shall take all such action as may be necessary or convenient to carry out the plan. All deeds, assignments or surrenders of leaseholds and contracts and other interests, leases, mortgages, contracts and other documents shall be approved by the commission.

b. The plan may include all the railroads or systems of railroads and controlling or leasehold interests therein which the commission decides should be included thereunder or may in the first instance include one or more railroads or systems of railroads, or controlling or leasehold interests therein and may thereafter, with the approval of the board of estimate be amended or supplemented at any time or from time to time, either before or after the completion thereof, to include one or more additional railroads or systems of railroads, or controlling or leasehold interests therein as the commission may decide, or there may be several plans each comprising different railroads or systems of railroads. The commission, if in its judgment such action is necessary, but only after a public hearing, and with the consent of the board of estimate and of each railroad company whose railroads or interests therein are included therein, from time to time may modify such plan after formal adoption thereof. The commission may further extend any period of time prescribed in this article or by it thereunder with like authority.

c. The grant of power herein conferred shall embrace, and the words "the railroad" as used herein shall be deemed to embrace, contracts and leases for the use and operation of railroads, including existing contracts and leases between the city and a railroad company for the construction, equipment, maintenance and operation of railroads under this chapter; provided, however, that the acquisition of any such contract so made by the city or its transfer to the city shall not operate as a merger or cancellation of such contract, unless otherwise provided in the plan, but such contract may be held in trust by the city for the beneficiaries thereunder, including the city, as provided in the plan until such time as the obligations in respect thereto under the plan shall have been discharged.

e. Railroads and interests therein may be acquired by the city subject to all or any mortgages that may be existing thereon. In the event that railroads or interests therein are acquired in whole or in part subject to existing mortgages, all the obligations of any mortgage subject to which the railroads are acquired in its discretion, may, and if required by the terms of such mortgage, shall be assumed by the city, provided, that any such acquisition and assumption shall in no respect increase, diminish, alter or otherwise affect any rights vested in the trustee or the bondholders under any such mortgage.

f. The plan and any contract, lease or mortgage made in pursuance thereof may contain such other terms, conditions and covenants, not inconsistent with this article, as the commission or board of estimate shall deem to be necessary or advisable, including provision whereby elevated railroads or portions thereof acquired by the city may be removed under arrangements between the mortgage trustees and the board of estimate.

g. After the approval of such plan, as provided in this section, and thereupon, if the plan is or is declared to be operative in accordance with its terms, the board of estimate may consummate the transaction by the execution and delivery of the deeds of conveyance and instruments of transfer, leases, mortgages, contracts and all other instruments and documents, necessary or advisable for carrying the plan into effect which shall be approved by the commission.

h. All the provisions of this article and all powers hereby granted with reference to railroads and properties and interests therein shall likewise apply with equal force and effect to recaptured railroads; provided, however, that nothing contained in this article with respect to recapture or recaptured railroads shall alter or affect any rights or remedies of the city or of any railroad company under any existing contract.

i. If, pursuant to a plan, the city shall become the owner or holder of securities of a corporation owning the railroads to be acquired under the plan, or the securities of a corporation holding the securities of such owning corporation, or securities to which such railroads are subject, such securities shall be delivered into the custody of the comptroller of the city. The city, acting by the board of estimate or by such person as the board of estimate may designate, may exercise such powers with respect to such securities as might any other holder hereof.