7. In constructing or maintaining any of the scheduled works, Network Rail may—
(a)deviate laterally from the lines or situations shown on the deposited plans to the extent of the limits of deviation for that work; and
(b)deviate vertically from the levels shown on the deposited sections—
(i)to any extent not exceeding 3 metres upwards; or
(ii)to any extent downwards as may be found to be necessary or convenient.