Most stores make their daily sales data available in the middle of the night. However, Apple, Google, and Draft-2-Digital don't make their sales available until 5am, 6am, and 10am Pacific Time (8am, 9am and 1pm Eastern Time) respectively.
You can control when your first email arrives (see the Profile tab of the Settings screen); choices are 2am PT (5am ET), 5am PT (8am ET), and 8am PT (11am ET); that email will report the stores for which we have data.
We will always send out another email when the last store is fetched. Additionally, if the last store has not been fetched by about 4pm PT (7pm ET), we will send an email including sales from the stores that we have gotten. If we are able to get all of your stores' sales at some point after the 4pm PT email goes out, we will send another email with all stores' data.