It's stretched length - which may be more than you can achieve pre-surgery, since the surgeon doesn't have to worry about things like pain and straining the tissues!
I was circumcised and about 6" pre-op, and got about 5.5" of depth. (However, my surgeon was Brassard, who prefers to stop around 5-5.5" and use the remaining skin for additional labia detail. A better instance for your purposes would be to know that the only woman there who didn't get 5" or more without a skin graft was both circumcised and under 1" before; anyone over that size had adequate donor material for reasonable depth.)
incidentally, when I went off HRT for surgery, I also saw all the "shrinkage" reverse... I'd been down to like 2" on HRT, but it bounced back to its original size within a week!