I took the car to the dealer and he swapped the solenoids from another car. This seems to remedy the P013 code, but brought up a P010 code!
The dealer then told me to leave the car with him so he could take it to his friend at the SimplyAlfas garage so they can have a look at it.
This was on Monday, not heard anything since....quite worrying. Seems a bit rum to have a month warranty then for the car to be in the possession of the dealer for some of that time!
I'm also assuming that any parts/work done to the car should be warranted separately -does anyone know if this is right?