I found the article , but it was pretty sketchy on details. Seems like weak reporting, wiht no sources cited and very little specific details given. Even weirder, this is the only article I was able to find that seems to be discussing these proposed changes.

Here's one problem I see: subchannels are not separate entities. Each station has a certain amount of bandwidth available, and the broadcaster can use all of that bandwidth for a single HD broadcast or use some for an HD digital broadcast and use the rest for one or more SD digital broadcasts. Therefore, the FCC can't take away the subchannels. They can reduce the available bandwidth, but I'd be hard pressed to see how they justify that. They'd have to cut it back from 19mbps to probably 2 or 3mpbs to force stations back to a single 480i DTV broadcast. The digital transition was pretty clumsy, but this change would make it look like a well-oiled machine. Before I believe the FCC is seriously considering cutting stations' bandwidth by a factor of ten, I'd like to see some more proof.