We have exact same problem,66 plate car with 19k on it. Started putting the EPC light on after being parked up through lockdown, then the EML as well plus "Stop start system error" on info display. Bell crank on turbo seized solid and actuator clicking like its trying to move but can't. Should Skoda not be sorting this as its obviously a common problem? especially on low milers.
Will have a go with the WD40 when its cold enough to get the heat shield off but don't hold out much hope.
Is it a variable vane turbo on these like the diesels have?