Like Chuck said. Looking at your plugs, mileage, some quide wear for sure. I was lucky, bent valve outside the garage idling. Machinist told me when milling out the quide on my right head, the quide just dropped out after minimum milling. Not trying to scare, just a wear thing. 215600km not bad at all. Don't think the unsceduled pit stop had anything to do with wear. Just some thoughts docc.
Cheers Tom.