I talked to Verizon tech support regarding this issue. The first support person was totally clueless about it. After insisting on speaking to his supervisor, I got a series of evasive responses. He would not reveal the cutoff date for CDMA service. He claims that the Samsung SCH-U340 will work after the cutoff. I informed him that his response was contradictory to the info on this forum. I don't know why the cutoff date is such a big secret. The live chat and the Ask Verizon services on this website are totally useless!! I know 5G is supposedly the best thing since sliced bread, but I just want to be able to use a dumb phone to make and receive calls. It would be nice to know when that will no longer be an option.
It's tentatively been planned for shutdown by the end of 2019, but since it's a ways out it could change. Prior to shutdown (usually about 1-3 months before) they'll notify all affected customers to provide options to continue service with another device however.