ISX15 regen question

I’m in CA so last year finally had to give up my great old truck for newer “emissions friendly” truck. Still not fully tuned up on this new system. So, here’s my question. I’m a local dump truck driver. Sometimes, my truck ups the rpms from 700 to 760. Is this a regen and is it normal? It’s a 2016 KW T880.

 

Forced regen gets my rpms up to 900. This just does it every so often. And I hear the turbo whistling too. Sometimes lasts about 20 mins. And it happens only when I’ve been doing local driving, and no freeway. Just bumping around town. When it kicks in it’s a ##### to go though gears as it throws rpm off. I was assuming it was some type of regen