[Newell Attack]

Michelin recommends that the tires be professionally inspected starting with the 5th year with, as you say, mandatory replacement at 10 years.

Actual longevity is very dependent on their "care and feeding".

Exposure to UV light vs covered or indoors, sitting for long periods of time vs weekly or monthly driving, full recommended PSI all the time vs running at lower than recommended PSI all contribute to materially affect useful life of any tire.

Sadly, lots of coaches sit outside with tires uncovered for months at a time and then are driven with little concern for tire pressure. Do NOT expect 10 years of service from any tire treated this way.