Glad to see you are now sorted Seamuss - a good message for for all that these gas appliances should only be repaired/serviced by corectly qualified and registered engineers. Your safety is paramount.
You must excuse us gas engineers for not stating on these forums what we think/suspect may be the problem (like the pcb) as it could encourage the public to break the law and try to repair gas appliances themselves. Trust us - this is not a ruse to keep us in work.
Glad you found a good 'local' guy and hopefully you will keep him on board and recommend him.
Have a warm and safe Winter. Thanks for updating.