We are only guessing. I'd guess it'll take 6 months to a year.
I'd say that is overly optimistic unless Maxwell has already successfully started making DBE cells in volume.
Just look at Panasonic they are already ~6 months in to turning on their three new lines that are just a faster version of their old ones... And they only think they will get them up and running in June... What if there are more unforeseen issues with them?