In my country, LC states that if I alter the strap, any repairs on other parts of the bag (e.g. Zipper, snao buttons etc) will not be entertained as it is deemed I had altered the bag in some way. The fact that the bag is the bag and the strap not exactly part of the bag baffles me with regards to this policy. I wish to reiterate though I am unsure whether this is an International policy or just unique to my country.
Despite my height, my medium Cuir also hits me at my hip which I am not really comfortable with. I had ordered a shorter strap elsewhere and will post how it works out. I know a lot of ladies order from Mautto.com too so that might be an option for you. I had also seen ladies tying a knot and effectively shortening the strap though I had never tried it.