looking for some advice to do with the control system for exhaust light

Greetings all!
I recently purchased a second hand fabia, 1.4 16v 2006. A week after picking it up from the garage the control system for exhaust light came on, so we phoned them up and they said its sometimes some air in the system causing the problem, anyway we drove down to him so he could get the error code and clear it and said it's nothing to worry about. This afternoon the light came back on again.

So we have a couple of choices, ignore it until closer to the MOT (about 6 months) or get it looked at again, either by driving the 50 miles again or by finding someone nearby.

What I'm wondering is if there is anyone else who has had this experience or know of anything similar happening, and what would you do?

thanks for any help! James