What length of hair should I have during the procedure when I have SMP to cover FUE scars? (Photo)

I had 6000 FUE grafts. Obviously the donor zone is heavily depleted! I will have SMP to cover my scars (see photo). What length of hair should I wear for the SMP procedure itself on the day e.g skin fade or longer, as I assume the practitioner will match the ink/dots to that particular style/length. I'm asking because id like to wear my sides both short and long in future - upto grade 2, but I'm worried the dots will only be suitable for one single specific length, and not for another length.