Those plots must have opened up after the current round of lottery had already begun. They will be available for bids when bidding opens up for the next round. The end of the current bidding round is several hours away, and will be followed by a 4 day results period. After this, the "currently unavailable for purchase" plots will be open for bids, as well as any plots which are vacated before the beginning of the next round.

This system ensures that any plot on the market will always be guaranteed to be available for bidders for a full 5 day bidding period.