I raised the point and it was really incredible how much the fabric had dropped: I cut away more than 5cm at the top when I pulled the cloth taught!
After I put it together and came back to it over the next few days, however, the skirt had dropped even more! I didn't want to change the point again as I had it sitting quite nicely otherwise. I therefore decided to unpick the opposite portion of the skirt and push all the fabric down.
I machined this back up but over the course of the following week still a little more fabric dropped. I have therefore decided to leave it for another week to get the most out of it as possible, then put the seam back together. Then all that will remain is the hem, and the seam finishing.