Joining the FR fiver club very soon.
Full EB or "on" will start exhaust braking as soon as you let off accelerator, given the RPMs and load are right. Under 1250ish rpm and low speed it may not activate. When it's on auto, only when you depress the service brake will the EB activate under the same scenario as above. Essentially it will let you coast and slow only when you want it to.
2016 Forester 3171DS Class C Motorhome
2016 Jeep Wrangler Unlimited Sport - Toad
1993 Mustang 5.0 Notch 5-speed