We (my wife, our four-year-old son, and me) are traveling ORD-LHR in Basic Economy on Wednesday the 7th. Prior to this morning, we had not purchased seats. This morning, I saw that seats had been assigned to us for free, but it looks like I can't change them for free, or even rearrange who's sitting in which seat in our block of three. Is this typical (being assigned seats for free six days before departure), and if so, is it because we're traveling with a minor?
Thanks!