I did post about this in the other thread and folks piled on calling me a conspiracy theorist, but in the letter JCD received from his editor, they said they were shutting down all outside columns. This is in fact not true -- other columns have continued since then and some other columnists have had the title listed in their author bios changed while continuing to have articles published.
Is it disingenuous, especially with someone who has been working for you in some form for a very long time? Sure. But I've seen a number of online pubs that go through changes with their outside contributors and communication is mostly pretty poor.