Thought I'd close the loop on this. After a 3 month wait to have the car looked at at the dealer (... 3 months!), finally took the car over for its booking. Their notes: Confirmed blowers are INOP when on anything higher than LO, carried out skoda diagnostics and no faults stored and no factory guidance. carried out function test and found blowers started working. removed pollen filter to check recirculation/fresh air flaps and found fresh air flaps working as required but recirculation flap was stuck closed. dash and cross member removal required to replace recirculation linkage and rectify fault. replaced re-circulation flap motor and tested - all functioning as intended. Needless to say the cost of the re-circulation flap was nominal. The cost of taking the dash apart was not! But, we are now back up and running, just for the cold weather to start to pass!