Replaced drive and HBO went away
My S3 drive was dying, so I got a new one from weaknees. Install was easy, redid guided setup, and everything worked except for HBO. Long story short, the host and data values were wrong at Verizon. Before we realized this, Verizon kept trying to restart the card, but it never worked. Finally, I had them read out the host and data values they had for each of my two cards and that is how I realized the values were wrong. They had some difficulty getting the right values to "take" in their system and I had to reboot the TiVo to make it work, but then it did. So all is good again...and I did not have to switch to the m cards.
Hope this helps someone in a similar dilemma.