How long does it take for Amazon SPAPI data to appear in my reports?

Timeliness in Amazon SPAPI datasets varies, with Seller Partner data being released 72 hours and Ads data being released 12–24 hours after the period closes

Once you authorize Analytic Index access to your Amazon Selling Partner API data, we begin to request historical data immediately. A full historical pull can take several days depending on the age of your account. Once your account is caught up, new data is available on the following schedule:

Selling Partner Data 72 hours minimum Controlled by Amazon
Amazon Ads Data 12 hours minimum, up to 24 hours Controlled by Amazon 

In most cases, Selling Partner Data will be available in your account approximately 72 hours from the close of the business day in question. Amazon Ads data will be available usually within 24 hours of the close of the business day in question.