With the acquisition of Alltel by Verizon Wireless, AT&T and ATN, we have been expecting the Alltel Back Door Voice Mail Numbers to be deactivated. Indeed some have, but we can't find a relationship between acquisitions and location.
In some places the access is now using the Verizon Voice Mail platform and others are unidentified. We haven't tried to see if these still-working numbers may now give access to nearby Verizon Wireless numbers. We logged a loss of about a dozen Alltel numbers. Some of the markets still working could be those switching to AT&T, so their future is still clouded.
Many Alltel customers used these numbers with their "My Circle" plan to make free calls to voice mail. We'll assume there are still many changes to come in this area. Fortunately, free calls to voice mail just isn't the big deal it used to be.