Pioneer NFTs cannot be unstaked until a specific number of Pioneer NFT gets sold. The specific number of Pioneer NFT that needs to be sold for yours to get unlocked can be drawn with the Linear Reduction Model Formula: (id <= 29999*(last_id-5001)/24999 + 1). Once 10,000 Pioneer NFTs are sold, all Pioneer NFTs will become available for unstaking. However, if you unstake, you will not be able to receive any more ISK rewards.