The B-Band converter is not for the HR10. It's only for those DirecTV boxes that are MPEG4 capable (those listed in the message you quote). Without the BBC, those boxes cannot receive from the new satellite launched earlier this year. The HR10 can't receive them no matter what.
I have no clue about NFL HD, but don't get your hopes up regarding it staying where it is.
I have no clue about NFL HD, but don't get your hopes up regarding it staying where it is.