You can win the Jackpot at any time. All you need is some luck. The Jackpot is USD 1,000,000, and both winning and losing bets can win. The only requirement for a bet to be eligible is that it needs to be USD 10 or higher. One more thing, the Jackpot is provably fair, which means that players will be able to verify if they won using a calculator featured on the sites. Anyway, if they win, they will be notified automatically.
To verify if your bet won the Jackpot you need go to copy the Bet ID and go to the Bonuses section on the sidebar. Then click Verify on the Jackpot banner and insert the Bet ID on the first slot marked as Bet ID.