Historically Verizon has not taken something like this away from customers - i.e., something a customer got that was the result of Verizon's mistake.Will continue to monitor over this and next billing cycle but fingers crossed!
This is a Verizon mistake, not an Apple mistake. All Apple's system is doing is requesting the codes from Verizon's system that are associated with your account when you go to add a line. Verizon's system is returning the UDP feature code when it shouldn't be. But that is due to a mistake on Verizon's end.
My 2 friends who have UDP lines on their family plans both received only More Everything plans to pick from when they tried to add a line to their plans. I wasn't able to even get that far as I only received an error stating my request could not be processed. So it doesn't work for everyone with UDP and it didn't work for me