I'm not sure about that, whether you can be considered eligible if you buy after the token unlock or not, only the team can answer. But I personally don't think that's logical. If anyone can be considered eligible for the airdrop by buying and transferring their amount to a wallet, what stopped someone from buying at day -1 or week -1, then hold it on a relatively short amount of time if compared to other people who had hold theirs for months.

Unless there is a certain period of "lock-down", like anyone who buy before December ends and lock their tokens ever since. This will actually boost the token price after the first dump, because there will be a lot of people wanting to get hold of their own SCT before December ends, much like how people wanted to get their BTC before a hardfork.