Thanks guys. i have contacted skoda Stockport again and they have stated its £350 not £250 to recalibrate! I have told them the front trim has fallen away, must not have been fitted securely and the sensor is faulty and requires recalibration under my warrantee period. They have stated that it needs diagnosis at £60 to see whether its covered by warrantee. i will cause a fuss tomorrow when i pick up my replacement grille sensor cover. My insurance does not ask front assist cover questions.
I ain't paying £350 for a recalibration. i cannot afford it. full stop.
Skoda have also stated that these things are really sensetive and any slight knock can affect calibration, so what's to say after I've had it done it wont fail again. Only had the car 3 months!