Here is a representation of what happens when you interrupt a regen that has already started (as opposed to a pre-regen - see my other video on that). Basically - in this case nothing happens. The regen will pick up again the next time you drive.
https://www.youtube.com/watch?v=o3J3QG9-Kko
https://www.youtube.com/watch?v=o3J3QG9-Kko