Teri, I've read as much as a person can read on this without going blind...lol...and here's what I've concluded:

It varies too much from person to person to make blanket predictions.

Exercise does not give metabolically obese/overweight people the same benefits as naturally thin people, so don't over exercise (besides, you'll likely get hurt and not be able to keep up unhealthy levels forever anyway)

If you lower calories, you'll lower your BMR--not a happy end result--so I'd advise not trying this.

It's possible that after a year or so at a new set point, you'll be able to shift slowly down to a lower set point.

It's also possible that we have a natural body weight and we'll keep returning there. The body may do ANYTHING to make this happen, like lowering BMR or shifting hormone production or whatever...a scary thought, as those shifts may lead us to worse health, rather than better as we fight our set point.

Because of that, it's a great idea to come to terms with the set point where you are now (even if you get a new one in 17 months that you like better). How? Doing body image work, getting therapy if needed to help with that process, coming to a place of more profound self-love, really looking at the women of about your age in the real world around you more than at the women on TV (real women just don't look like that!) In fact, it may be best to put the TV in a closet, toss out the "women's magazines" (the women's-torture magazines, I think of them as), watch limited movies populated only with skinny women, challenge any unhealthy and unrealistic thoughts as they crop up, and focus on the real world around you instead.

It can help to set other goals--our dress size is such a tiny, tiny, TINY part of who we are, we needn't let it rule our self-concept. Enjoying life is the greatest victory of all.

If you havent read Forsberg's Adiposity 101 on line, and you want more good info, that's where I'd advise to start gathering it. I also really like the Garner article I linked to a couple months ago in research/media watch.
HTH