How many miles on the truck?
The Regen timing seems normal. My most recent Regen was at 403. Period to that I've been hovering at around 350.
If you haven't already, replace your MAF sensors. And this may be the result of not monitoring your Regens and likely turning your truck off mid Regen, not allowing it to fully Regen, etc. Over a period of many thousands of miles.
You won't even need an extended warranty for emission stuff, I think emission stuff warranty is 8 years or something like 120k miles.