19.—(1) In addition to making an application for capacity in accordance with the annual timetable process described in regulation 17 an applicant may submit ad hoc requests for infrastructure capacity in the form of individual train paths to the infrastructure manager.
(2) The infrastructure manager must respond to a request described in paragraph (1) as quickly as possible and, in any event, no later than five working days from receipt of the request.
(3) The infrastructure manager must make available, to all potential applicants for such individual train paths, information about available spare capacity on the network for which he is responsible.
(4) The infrastructure manager must, including in the case of congested infrastructure, undertake an evaluation of the need for reserve capacity to be kept available within the final working timetable to enable him to be able to respond rapidly to foreseeable ad hoc requests for infrastructure capacity.