Mother plants: pot size progression or directly to 11L ?

Yes do it progressively, like a normal plant, and in each transplant you can cut a big piece of the roots, after that water with a bit of voodoo juice or something like that, and once youre in your last pot, you can just once a month cut a piece of the roots and put it back in the same container with some fresh soil, i had a mother like that for more than a year