Since the update before or at the start of combat Pillar of Frost will show cooldown of 11H, 10H, 4H etc. It will count down a bit after the start of combat then wont reappear with that issue after the first use and then go back to normal.
Bingo176 commented
Still an issue, believe it was introduced in the 7.2 push. Have yet to see it on other chars.