17.  In the assessment of any sums payable to Network Rail under this Schedule no account is to  be taken of any increase in the sums claimed that is attributable to any action taken by or any  agreement entered into by Network Rail if that action or agreement was not reasonably necessary  and was taken or entered into with a view to obtaining the payment of those sums by the Authority  under this Schedule or increasing the sums so payable.  18.  The Authority and Network Rail may, subject in the case of Network Rail to compliance  with the terms of its network licence, enter into, and carry into effect, agreements for the transfer  to the Authority of—  19.  Nothing in this Order, or in any enactment incorporated with or applied by this Order,  prejudices or affects the operation of Part 1 of the Railways Act 1993.  20.  The Authority must no later than 28 days from the date that the plans submitted to and  certified by the Secretary of State in accordance with article 51 (certification of plans etc.) are  certified by the Secretary of State, provide a set of those plans to Network Rail in the form of a  computer disc with read only memory.  (a) any railway property shown on the works and land plans and described in the book of  reference;  (b) any lands, works or other property held in connection with any such railway property; and  (c) any rights and obligations (whether or not statutory) of Network Rail relating to any  railway property or any lands, works or other property referred to in this paragraph.  72