Part of an email I got:
"To continue to provide this best-in-class travel rewards product and to simplify its structure, we'll be making the following changes, effective August 16, 2016:
Redemption bonus changes
The bonus miles you receive when you redeem for travel statement credits will be reduced to 5% miles back. At the same time, we’ll expand the 5% miles back to ALL redemptions — including travel and cash back statement credits, gift cards and merchandise. That means, every time you redeem miles, you’ll get 5% of your miles back to use toward your next redemption (for example, redeem 20,000 miles and get 1,000 miles back)."