Temporarily premium items (spoiler, perhaps)

Correct me if I'm wrong. But I understood that on the 21st there will be some limited items available that can be bought with tickets. And that there are special tickets available when you buy a premium item. This kept in mind, should I wait for the 21st to buy King Winter since it is a premium item and he is available until the 24th? Or are these tickets not given away when you buy a limited time item such as King Winter or the Burns skin, so it doesn't matter if I get them now or wednesday...?