We will soon be updating the World of Tanks in-game store. As of 16 January, 2012, the Type 59 premium tank will be removed from the in-game store after the server restart which will take place at 5:00-5:30 GMT. While the tank will not be available for purchase, all existing Type 59 owners will keep their tank intact.
This decision has been made to ensure a healthy gameplay balance at higher tiers, and also to encourage a wider variety of tier 8 medium tank usage. Should the T59 become available again through special events in future, we will make sure to announce such events ahead of time.