TiVo, Cablecards, Channels I am paying for and cannot receive

There are several posts about folks with Tivos using cablecards that, like me, found that their favorite channel(s) that they were receiving fine are now showing up as black screens.  Seems that in some cases the SD version of the channel works but not the HD version.  In some cases there is no SD version of a channel so we are, in effect, paying for a channel that has been taken away with no recompense.  I dont not have an analysis at this point but it is more than a dozen in my case.  My local Xfinity Store seems to have no clue about what this is yet the Xfinity website and the TiVo site make reference to a digital tuning adapter that addresses this issue.  Seems these channels either were converted to IP channels or always were IP channels and the current Comcast cablecards cannot decode or handle them.  As a result, all Tivos with cablecards cannot receive these IP channels.  In my case, several of the channels I was watching were converted sometime this past year to IP and I, in effect, lost them.  No notice, no discussion and no concern.  So my attempts to discuss this and politely ask for a digital tuning adapter to address the problem are met with confusion, attempts to give me the wrong piece of equipment, suggestions that I just use one of their less functional DVR boxes or have a technician visit my home.  THIS IS RIDICULOUS!  Why can we not just have a better cable card or just simply have someone say - Oh sorry, here is the DTA you need to address the problem with simple instructions to attach it.  That would earn some good will and show a little customer concern.  Do I have this issue described correctly and please tell me someone had a positive solution that we can cite and get this matter settled.