I have noticed that on some reviews, the provider's ad website, email address, and/or phone number disappear for some reason.  

I'm guessing that the provider didn't like the review or the score or both and contacted TER requesting that the review be deleted, which was denied, but to minimize the damage, the contact info was taken down.

Or

The provider's website is no longer valid, so TER deleted the link.  The same with email and phone.

TER will award any VIP a couple of day of VIP for finding things like links and phone numbers that no longer work, and reporting that to TER.

 
It comes in especially useful when using the filters to find providers in an area because you can filter out sites that have faulty links, thus saving you time from having to do the research yourself.

Thank you, mrfisher.