Platinum was like 200$ and Platinum 2 was 300 or 350$. Platinum 3 I think was 500 or 600$. Havent gone higher...
Are you sure about those number? Frankly speaking I do not understand how they calculate the amount for the bonus once we get ranked up.
I'm platinum 2, as I remember I did not get that much when I reached my platinum 2 rank.
If I remember it correctly, it was like a half what you mention here. If what you mention here is based on your own experience, now I wonder how is the calculation for the bonus?