Join Date: Jul 2007
Location: San Francisco/Sydney
Programs: UA 1K/MM, Hilton Diamond, Marriott Something, IHG Gold, Hertz PC, Avis PC
Posts: 8,156
And just because dhuey didn't explicitly mention it, you will need to re-clear security in order to get from the Centurion lounge back to International A.
Intl A security can be a real mess depending on the time of day - especially if you don't have priority.
Presuming that you also have a Priority Pass, there you can also access the Air France/KLM lounge in International A. Nowhere near as good as the Amex lounge, but it saves the extra trip through security.