Downshift sensation

At that low speed it's probably the regeneration ceasing to operate efficiently (or shutting off), when the regen stops the deceleration will reduce and it will feel like you sped up a little, I have noticed it when braking lightly. Just before you stop (ie 1-3mph) you need to press the brake peddle a bit more.

Parax is correct. At very low speeds there isn't enough regen power generated to operate as an effect brake and so it switches to mechanical brakes for the last second or two when stopping.

Ideally if should be seamless but all the EVs I have driven it is slightly perceivable. It seems a little more noticable on the Ampera than on the Leaf.

It can catch you out the first couple of times so leave extra room between you and whatever is in front when stopping until you get used to it

I noticed this effect as soon as I first drove the Ampera but now it's second nature.

I always marvel at how the brain copes with change.

I drove a regular (hire) car on holiday recently and thought how "strange" the brakes felt.

Big Paul