I believe it only has to be refueled once, at 25 years. It was built for 50 year service.

USS George Washington CVN-73, christened in 1990 just finished its first and only nuclear refueling.

"Refueling complex overhauls are performed at the mid-point of a ship’s 50-plus-year lifespan".

https://www.navy.mil/DesktopModules/ArticleCS/Print.aspx?PortalId=1&ModuleId=523&Article=3408521

I believe it only has to be refueled once, at 25 years. It was built for 50 year service.