Some cords are longer and some are shorter than others, I find when delivering a baby it depends on the positon the mother is in, most times the mother can cut it if she wants but if you birth on your hands and knees and you have a short cord it makes it hard to pass the baby through the mothers legs for the cord to be cut. I think the best thing to do is to wait until the baby is born, you can put in your birth plan that you want to cut the cord if able to at the time
Good luck