You can buy the tickets now through 1 407 WDISNEY or buy going to their website. One thing that bothers me about people saying that the tickets didn't sell out until much later in the year is that the tickets went on sale so much earlier this year. I have to wonder if that might not change the availablity status of the MVMCP tickets.
I bought mine the first day they became available. This is only because I wanted to make sure we had something to do our first night at WDW. I am guessing that Pop Century's opening may cause a lot of guests to arrive on 12/14. I wanted to be sure to have my tickets for that night. Also, if it rains buckets, I want the chance to swap tickets out for a day later in the week. Mickey