I don't think anyone has a 'AAA' mandate anymore, just a requirement that the market for whatever instrument you hold be deep enough to absorb your selling before going "No Bid."
From Bloomberg, August 2:
The fallout from Fitch Ratings’ downgrade of the US puts the focus on the countries still holding onto the coveted top credit grade.
Economies with the highest credit rating at S&P Global Ratings, Fitch and Moody’s Investors Service include Germany, Denmark, Netherlands, Sweden, Norway, Switzerland, Luxembourg, Singapore and Australia. Canada is rated AAA by two of the ratings companies.
Fitch’s downgrade of the US sovereign follows the cut by S&P in 2011, leaving Moody’s as the only major rating company keeping its top-tier grade for the world’s largest economy. Fitch said the cut reflects expected fiscal deterioration and a growing government debt burden after repeated debt-limit standoffs....
....MUCH MORE
Related:- Biden Officials Decry 'Bizarre and Baseless' Fitch Downgrade, Blame Trump
- Capital Markets: "Fitch Roils Markets"
