How long will it take to lose a stoneWatch
July is a very manageable goal, but don't have this number set in stone. You might reach 9 stone and be perfectly happy with how you look. Also keep in mind that muscle weighs more than fat, so if you're working out a lot or anything then that may be where some of the weight is coming from now!
Don't do it. You are perfectly fine the way you are at the moment. You should instead, work on maintaining that.
Why don't you try some strength training to tone yourself up a bit?