Sometimes its not even DDOS but its basically tons of people flooding the autobot to get the winning roll.
I have pretty much given up trying and winning a milestone number because its impossible to time it properly.
Even if you calculate that there are 100 bets/second and when it gets near the milestone number, in that minute it will go up to like 500 or 1000 bets/second which are all mostly bits competing to get the winning number.
What needs to be done is limit the bets to like 1 bet/second during that hour that the milestone numbers will appear. It will give everyone a more equal and fair chance.