Chain lube every 500 km on the 450, or are you stretching it out?

Manual says clean and lube the chain every 500 km, earlier if it's wet or dusty. I do track days plus the odd gravel trail so mine is never really clean for long. Saw this on Team-BHP where a guy stuck to the 500-750 km routine with Motul and got past 30,000 km on stock chain and sprocket. Anyone here actually following that interval religiously, or do you just degrease once in a while and top up lube as needed? What's working for you.