This was last fall.
My dealer recommended an air filter change after I brought the subject up. I changed the filter based on recommendations here, but to be fair, there wasn't any significant dust on the pipes from the original filter.
The specific dealer concern was the Jericho trails up in Berlin NH where the dirt has been pounded into a fine powder from all the heavy ATV traffic. In addition to that, many of the rail trails around the state are very dusty. The service dept had several RZRs in the shop that day with bad motors from dirt infiltration, and said this was common, so it isn't just a CFMoto issue.
The service manager said that CF MOTO was very responsive to his warranty claims.