The WTS has put the WT/AW on audio cassette and then mp3 audio for years. A lot of the friends listened to the cassettes in their cars while commuting.
The society may combine the WT/AW bound volumes or discontinue them but neither of these two alternatives change the fact that :
a) The regular mp3 audio or cd audio of each issue will continue to be issued.
b) That the KM already stated that the WT CDrom would be updated and available yearly.
There are a lot of the friends who don't order the Bound Volumes any longer because the WT CDrom provides the research material they need. Most dubs save the current year of magazines for meeting preparation and such and replace them with the bound volume or the WT CDrom.
Can you imagine a cd audio of the entire year of WT/AWs? It would be a major multi-disc set with very little use for preparing for the meetings. If you've been a witness you know that you use the older magazines (usually within the past year) for meeting part preparation.
It seems that this "rumor" blends two issues into one. Perhaps no more WT/AW bound volumes and current issue mp3 audio becoming cd audio.