Not if he is using that 100,000 mile Super Duper Wonder Amazing Amsoil. Course Briggs has them beat out with no oil changes ever LOL.Read your Engine Manual & Operators Manual cover to cover. You're way overdue on oil changes.
bought it new, and it now has 130 hours on it, original belts but it is also only a year old.Yup agreed on keeping spare belts. Especially if your mower is a known belt eater.
Oil is pretty tough at a yearly dump and fill. Now if I was a commercial guy or had some huge yard that took many hours to cut then I would do the hour thing. Probably follow the extreme dusty environment recommendation as in early oil dumps.
slomo