Yes it can roll back.. but its not as bad as it sounds. Nor does it happen in every circumstance.

Occasionally when you come to a stop and autostop engages.. If you 'lightly/slowly' take your foot off the brake, the vehicle may begin to roll back. If you quickly take your foot off the brake and apply light pressure to the accel pedal. You will not roll back. The drive engages and you'll move ahead just fine.

While it is a bit bothersome.. i've grown use to it. Its similar to the braking quirk. Where as you decelerate and come to a stop. Near the tail end of the stop.. i.e. ~10mph or so and slower.. your regenerative braking will suddenly cease and it feels like the car's breaks have let loose somewhat and wants to jump forward. In reality the regen braking switched to full ABS braking. The feel changes, and there is a tiny fraction of a second where the full braking system needs to catch-up and make up for what the regen braking was doing previously.

The best protection for this braking change is to brake slowly and carefully and maintain a good safe distance between you and the person in front. Good practice in any car, not only the HCH2. It also ensures you get maximum regen energy from your brakes, and reduces wear and tear on your pads.

I hope I worded that well.

-G