I have only gambled on this platform once. I checked my email after seeing your post but there was no bonus notification. I think they only gave it to their active and regular gamblers. If it was FCFS then you probably missed it because the budget they had was already claimed by other gamblers. But if they gave their anniversary gift then of course it should have been a specific budget for individual users. And the email would have been sent only to those users who were eligible to claim that bonus. I don't know what is actually happening.