Aw shucks 
My discharge letter said I was advanced 6mm, but my overjet was at least 8mm (it was originally 11mm but was measured at 8mm after 3.5 years in braces) and my lower teeth now sit directly below if not 1 or 2mm in front of my top teeth so I'm not sure
I am sorry I am not super familiar with the british system so had just skimmed over NHS. I now understand. It is a bit different when dealing with private sector surgeons and they are more apt to have follow ups to address aesthetic concerns. But even then they are 75% of the time in denial mode.Still if your bite seems unsettled I am sure you can go back to see your surgeon but the way you describe it probably your orthodontist can fix this.
Regarding the jaw line issue , even though you look like you are healing great there is swelling which is still to go down. 3 - 5 months from now things ought to be more settled. You could consider a submental lipo to address the area if you want to.
Probably you should have been advanced slightly more but maybe because the surgeon elected to not move the upper jaw he felt constrained. But seriously you look beautiful and even before you were so , pixie like. Imho very forward jaw may be detrimental to that kind of feminine beauty.
