Talked to a local store manager after a chat with a rep. Do I need a new SIM card to transfer number after alternate upgrade? They do not know.
OK I call customer care 1-800-922-0204 and a fairly knowledgeable tech said that a transfer can be done on line. The SIM may or may not be actually installed in the phone. I cannot imagine VZW requiring people to install a nano SIM themselves. The tech recommended calling the 800 number form another line and they will go through phone number change and activation. He said to NOT turn on the phone. You will need certain information during the activation process. So as soon as the phone arrives I will be calling the 800 number. You obviously do not need a new virgin SIM. Great news - I think. The tech sounded very sure of the process. Let's hope.
Tech also said that the basic phone that the alternate update was done on will not know that anything has happened - other than the fact the account for that line will show a 2-year agreement.