drrjv wrote: If not Roll Over, it would be nice to just have Data turn off when I hit 40, but that would not be in Verizon's interest either.

IT is impossible for any carrier to shut off data at a particular point because of the way data is collected and reported by cell towers.   Each time your phone connects to a cell tower it starts recording data use.  It stops when you leave the tower area, connect to wifi or turn off the phone/mifi.  It reports the use hours later in batches, frequently during non peak use hours.

It's like writing checks all over town.  The checks don't take money from your bank balance until they are deposited or cashed by the payee, which could be much later than when you wrote the check.  If the total of the checks exceeds your balance, your account is overdrawn.