Big XII, and now that I think about it, even before that when BYU was starting play in the Big XII. So, it's pretty consistent with what he has been doing since then, so I don't see him changing now.
From everything I now, he's a KU fan. He is annoyed/irritated by the better-than-you, we're going to run the table in the Big XII, and the Big XII is just a temporary stop for us on our way to the Big 10 schtick that has been prevalent from many of their fans and especially their more active social media posters. They've irritated him enough that Utah is usually his favorite target of derision. His posts usually make fun of the schtick I mentioned above.