Loss of Verified Provider Status

I recently noticed that a provider I've been interested in is no longer a "verified provider." Her account is still here so she's not banned and her old reviews are still around. She had a showcase and was a "verified provider" but now her showcase is gone and she's listed as a "registered member." Why would a verified provider ever lose that status? Is this something that automatically takes place after a certain amount of inactivity (she hasn't posted or been reviewed in quite a while) or does staff revoke verified provider status for some transgression or maybe something else explains it?

If she hasn't visited the site using her VP account for over 90 days, her account reverts back to Registered member/valued poster. All the perks of the VP upgrade are disabled including the showcase.

The date of her last review does not affect the standing of her VP account.