we have a family plan and one member would like to remove his number from our family plan and get his own plan elsewhere. He has an unlocked phone which he purchased separately from at&t and then used the sim card from his previous at&t phone on our plan. However, another member on the plan used the first members "upgrade" so there is an active installment plan on the first members number on our monthly bill.
So, what happens if the first member ports their number to another carrier? Does the installment balance on their account (for a different members phone keep in mind) need to be paid in full upon removal of the line from the family plan? Or can the active installment plan simply be transferred to another number on the family plan?