I just got this txt from Verizon on my flip phone (as I’m still waiting for my Librem5 and might want to try and use Verizon with it). Note that the emphasis below is mine:
Hi it’s Verizon, as part of the transition to 4G LTE & 5G, your 3G (CDMA) and 4G Non-VoLTE device will receive limited troubleshooting support starting 1/1/2021. After this date, for additional troubleshooting support, please go to https://www.verizon.com/support/brands.