The $250 can be cashed out straight away after player receive it. There is no terms behind the bonus, players are free to use it as they wish. I can say like this because I experienced it myself. Some other players also said the same at Stake's ANN thread. I am sure most players cash it out directly although not the whole amount as what I did. I cashed $200 out and played with the remaining $50.
Damn, that’s pretty cool! But I guess, this is probably only for a limited number of users, right? Like those with a high VIP ranking? The rule about mandatory verification to level 2 before the end of the year applies to everyone, but not everyone is actively gambling. So, it’s likely just a perk for selected users who are more involved.