This sounds more like a network issue than a BlackBerry issue. If the signal at your house has gotten weaker, either from a down tower or new construction blocking a tower that served your neighborhood, it would explain losing the 4G signal easily. Also, if you updated the software on your Z10 recently there could be an issue with the new version and the 3G/4G signal handoff.
I agree it seems more Verizon related than phone related. That said, right now its 4G LTE, but I find that it occasionally slows way down, and I see that its down to 3G. Then later it will go back up. I do notice that most of the time, but not always, a firm reboot of the phone (turn off/on) tends to bring it back to 4G LTE. I agree that it may have started after a Verizon-based update to the Blackberry Z10. Is there an expected Verizon update to fix this? I don't appreciate having to pay for 4G LTE only to have excuses as to why that isn't always the case. The phone's 4G LTE had always been reliable until the last many weeks. Its frustrating to pay for something I don't always get, and I pay a high price for that, too! I've always been Verizon on all my phones over many years, which have always been Blackberry. I love my Z10 unit, but am less happy with Verizon every year. Come next March, when I can purchase a new phone, I will be examining my options to see whether I stay with Verizon or move to another service.
I would appreciate your assistance in finding out why this change has
happened, and let me know whether to expect a fix to this anytime soon.
Thanks for responding back to me. --Ken
Just a thought, but have you tried installing a new Sim card? They are free at any Verizon corporate store. Sometimes that could fix the problem.