I just spoke to ed today regarding the plugs on my car as the tips on those were white and actually started to melt after my last cadwell track day
never mentioned your car gaz but he said with mine it could have been down to an alternator failiure (which actually was the case) and current drop causing a meltdown.
might be better to take a closer pic and send it to him and see what he makes of it as in all fairness if there is a possible problem its better for him to sort it now before the possibility of any damage but if he says there ok then you have to go with that really
never mentioned your car gaz but he said with mine it could have been down to an alternator failiure (which actually was the case) and current drop causing a meltdown.
might be better to take a closer pic and send it to him and see what he makes of it as in all fairness if there is a possible problem its better for him to sort it now before the possibility of any damage but if he says there ok then you have to go with that really