There is a difference in changing the payment date and changing the billing cycle. Did Verizon Wireless actually shorten your billing cycle? You can compare your current bill to an older bill to see if this is the case.
Another carrier that I use changed the payment date to be four days earlier than it had been. However, my billing cycle was unchanged. Hence the same amount was due, just on a different date.
With Verizon, the bill is due 5 days before the Bill Cycle ends, when you change the Bill Cycle it changes the due date as well, however, you are billed for a full month, regardless of days, but the average is 30 days. So if your bill cycle is on the 2nd, it's going to stay the 2nd no matter how many days are in between to reach the 2nd.
That was my point, that the billing cycle still has the same number of days and only the payment date has changed.
According to what you are saying the billing cycle dates are changing, as well. If that's the case, then there has to be a longer or shorter billing cycle out there somewhere, which is why I suggested that the OP compare an older bill to the current bill.
Plus, one more thing I'd like to add, if they do bill on a 30 day average month, how would you feel to be CHARGED the extra day in the months that are 31? They definitely don't do that, so it pretty much evens out from what I can tell.
A little bit of both I suppose, just kinda clicked the closest thing, I guess I didn't have much to say about your response because it's entirely true. But your input for the response would most likely help them too.