We are using the google adx apis to download campaign reports from google. We would like to know the frequency with which the data for these campaigns gets updated on adx so that it would be convenient for us to pull the data accordingly.
Re: Reporting frequency
In general, there is a three hour reporting delay with AdWords. However, some reports (like those on the Dimensions tab) can take up to 24 hours to process.
I'm not quite sure how the API would affect these numbers, you may want to toss it out to the AdWords API community, but in general, the above numbers are what I go by.