Originally Posted by
Upupintheair
I am a dual citizen too, have my US passport in API but actually only travel to and from the US on that passport. All other travel, mainly Europe, I do on my UK passport, never update the API and has worked for me for years.
That will work for one or both of two reasons: as a US citizen you are able to enter the country concerned and are in good standing with those countries; secondly these are countries that don't process API information. You have to be a bit more careful with some other locations, Australia is one that comes to mind. You are of course required to use your US passport on travel to the USA.