I’m fairly certain there are folks on here who have been monitoring the regens with 3rd party devices and reporting 400-500mile range between regens when burning closer to stock fuel efficiency numbers.You have had at least 4 regens in that time, possibly more. You will know based upon the real time fuel mileage indicator. Also, you can smell it and hear it. The latest diesels with urea, as mentioned, are going through a regen at least every 200 miles. The older ones with DPF but no SCR were doing it as frequently as every 80 miles. If you do a lot of city driving, it will be more frequent and of the "active regen" variety. More highway and it will be "passive regen."