NAB - Changes to points earn rates and caps due to RBA regulations?

From 1 July 2017 we’re making some changes to the points earn rates and cap on some of our rewards credit cards in response to new regulations being introduced by the Reserve Bank of Australia.

I tried looking on the Reserve Bank of Australia for the new regulations but couldn’t find anything. Since NAB decided to change my QFF linked Amex to 0.75 point/$1 I’ve decided to get the no annual fee 1 point/$1 directly with Amex (low income so can’t apply for anything better) but I’ll still keep my Visa card with NAB purely for the places that don’t take Amex (grr Costco).

Anyway do you know what regulations NAB is talking about? Are other banks affected? Will American Express issued cards also be affected?

It is regulations that cap the amount of interchange fees that can be paid to the bank that issued your card. It affects Visa, Mastercard and bank issued American Express cards. It does not affect directly issued American Express cards, or Diners.

The specific standards are referecned on this page