No, I believe that you can buy and sell individual sessions and/or full packages starting in February. I don't recall this being the procedure when I went in Atlanta. I was selected via lottery for 4 full session packages that year. I broke them up into individual sessions and sold 2 of my 4 for double face value so I essentially went with my wife for free. Unfortunately Duke lost to Louisville in the E8 that year, but it was a ton of fun regardless. I will say this, most fans wait until they know their team is in it before they purchase. That means that prices for tickets will stay relatively low until the week leading into the final 4, at which point they will jump way up. Here's 2 tidbits for those considering:
1. Buy early and get them cheap.
2. If Duke doesn't make it and you don't want to go, sell them in individual sessions rather than all session package. The finals tickets may not sell until Sunday or Monday, but for whatever reason the market for individual sessions spikes well above full sessions. Meaning that it was cheaper to buy a similar situated ticket as an all session package than it was to buy one individual session, which makes zero sense, but true.