The question is why did you purchase the computer if you knew you were expecting to exchange it later?
Anyway, you normally could return within 14 days and exchange to whatever you want, however, the new MacBook Pros have a vague shipping date of "2 to 3 weeks", which means that it won't be at least two weeks before the MBP with touch bar even hits the Apple Store shelves, so the return period will be already over by then.
I suggest that after one week or so, if you still want the upcoming MacBook Pro with touch bar, backup all the data, return yours while you can, and then wait a few weeks for the touch bar model to be released.