Wondering if any other Comcast users in Boston have had the following issue:

Last week, I noticed that NBA TV HD (channel 817) and also MLB Network HD (channel 818 I think?) mysteriously disappeared, and were replaced by a couple of the local Spanish channels.

They are still there in standard def I think, but I usually watch NBA TV HD and one day it was just gone.  Haven't had a chance to call Comcast, but I was wondering if any fellow CBers knew what the deal was?

Thanks!