Author: H.User1325 (29 Dec 16 3:20pm)
I have no inside information but the way I read the three comments:
The IP was blacklisted at sometime before Nov '15.
Around 25 Nov '15 the owner of the IP fixed the problem and requested that the IP be taken off the blacklist.
After evaluation, PHP said they would white list the IP and then did white list the IP.
Everything went fine for a year, until 2 Dec '16, when there was more bad action from this IP, i.e. as a mail server it looked like a directory attack came from this IP
As a result the IP was removed from the whitelist.