I have booked an international award ticket for three pax. Since all flghts/dates are the same, we are all on the same PNR. Now, if one of the pax changes flight dates for one segment, will that break this whole "single PNR"?

My reason for wanting one PNR is because I am AA Gold but the other two pax are not. So this way I have been able to select exit row seats for all of us.