I think I may have found the solution...
Replace your 12v battery (the "regular" car battery in the front engine bay).
I had the same issues as people described in the numerous posts here. I would characterize it a bit differently however. To me, it felt like whenever I brake, the regen braking would kick on and off. This would cause moderate to severe jerking of the car when coming to a stop. I tried all the solutions posted here with little success (turn off traction control, release braking, etc., update software). The issue would always return.
Desperate for a solution, I took it to the dealership AGAIN and explained what was happening (for the fourth time, now out of warranty). This time the only "code" to show up was for an old low voltage fault of the 12v battery. Luckily, the dealership tech I got this time had seen this issue before, and as weird as it sounds, told me that the 12v battery effects the brake controller. I have a 2012 Leaf, so around 4 years is about how long a car battery lasts in normal cars.
Since replacing the battery (you can do it yourself for around $100) I have not seen this issue return. Hope this helps.