I'm tryign to remember when I noticed my first difference. I can't tell you how many pounds it was, but I do remember calling a girlfriend from my car outside the gym and leaving an incoherent and babbling message about how I have CHEEKBONES!!!!!!!
In retrospect it was silly ... but she also lost a lot of weight and so totally knew where I was coming from.
But the point is that it will sneak up on you - and at some point you'll look into the mirror and go "oh my gosh! collarbones! cheekbones! whoa!!!"
Edited to say that my weight and goals are very close to yours, and I think it was right around when I hit 200 that I first noticed it.
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