said by CharlesH1: Am I to understand that at any time, I could get a letter from at&t saying that I must sign up for U-verse internet, and get a compatible modem?
No, you will recieve a notice saying in the next 30-45 days your service is ending. YOu have two options
1.) let the service run out- disconnection would happen anytime at day 31 to day 45.
2.) order uverse internet service and transfer your existing service to the Uverse IPDSL/VDSL network.You would need a compatible modem as the legacy DSL modem will no longer work on the current Uverse IPDSL network. There is some modems on ebay that will work or others that people have sold ex. 2wire 3600 hgv, etc..
The choice will be yours.