This reminds me of when I lived in the east midlands and needed to get to/from LHR, the public transport would entail, to refresh my memory I've just checked it out on traveline.info:
A 10 minute walk to the bus stop
A 46 minute bus journey
A 9 minute wait at bus stop
A 3 minute bus journey
A 5 minute walk to rail station
A 22 minute wait for a train
A 28 minute train to Luton
A 27 minute wait for a coach
A 1 hour 25 minute coach to LHR
Total journey time 4 hours ... Or as I opted ... F' that for a game of soldiers and hire 2 one-way hire cars.
So any train, bus or coach service are only useful for those living on the route(s) and it's not just SEN that may have such a problem, even LHR was a hightmare to get to for me.