If the flight numbers were staying the same you would be able to access the YSYC website however because they are changing to TCX123 TCX124 example for long haul, Egypt and Turkey with three numbers and TCX2014 and TCX2015 example for short haul the website doesnt support the new format yet but will do very shortly.
Updated New Flight Numbers from April 2011 due to changing flight planning software + upgrade of YSYC
TCXxxx - Longhaul flights + flights to Turkey and Egypt + Any other countries that dont like 4 numbers
TCX10xx - Flights from Gatwick
TCX20xx - Flights from Manchester
TCX30xx - Scottish Flights
TCX40xx - Flights from Birmingham
TCX50xx - Flights from East Midlands
TCX60xx - Flights from Newcastle/Teeside
TCX70xx - Flights from Stansted
More to follow