Does anybody know if I'm required to pay off my S9+ with T-Mobile before trading it into Samsung for the $550 credit? I don't want the open financing to make my Samsung credit invalid, but I also don't want to close my T-Mobile financing because I'm afraid I'll lose the $15 in monthly credits for another year. Every time I call T-Mobile to verify if I'll still receive the credit after paying off the EIP, I get different answers.