You can easily take a frame out of 10 frames and space the 9 out. You can't easily add a frame if they have drawn it for 9 frames because they will draw honey sticking out and that will not have a beespace when you squeeze them back together. If they drew it as 9 I would leave it alone for now. It's one of the reasons I don't like 9 frames in the brood chamber. They won't draw the face out consistent and if you juggle the frames around you end up with honey sticking out blocking some brood emerging somewhere. I prefer to cut them down to 1 1/4" and put in 11.
I agree completely with Michael Bush's description of the situation and I am working at shaving my end bars to 1-1/4" wide as I work at changing the genetics of my bees (but that's another story). Though, instead of an extra frame I plan to install slatted racks on the sides of the brood supers. I've already been testing this and have found that the queen will often lay even on the outside of the outermost combs, so with 11 combs you have 22 comb surfaces (usually 20 possible with brood) and with supers with racks you have 10 combs, 20 surfaces (20 possible with brood). Plus there is extra space for ventilation and bees. Sure it is a little more bothersome to build and install the racks, but I really love to tinker with the bees.
In honey supers I like to use 9 or often 8. About the same amount of honey in 8, 9, or 10, but I'd rather extract it from 8 rather than 10, saves a little bit of time and effort.