This change was implemented nearly two months ago, posts were made about it. That you couldn’t be bothered to pay attention to the update isn’t Blizzard’s problem. Things are apt to change over time, and if you were uncertain then perhaps you should have checked the Blizzard store before putting money into the balance. Now, if you add $10 more to your balance, you can purchase a 60 day block of time for $29.99 (I believe that’s what it is.)