How soon are updated customer attributes are available in Target Standard audiences after uploading files into People core service on Sep.13.2019 5PM EST?
It's been a while since I've done a deep dive into one of these issues but If you are uploading the data in the Customer Attributes interface I want to say it was 24-48 hours. If you built out a segment in Audience Library the rules would kick in within a few min and I think the Audience name would show up in Target within a few min. If you shared it from Analytics as a historical audience, it would take longer.
I'll see if I can get someone with a bit more recent experience to chime in here as well.
Per this KB article: Audience creation options in Adobe Experience Cloud
Audience are actionable after:
Experience Cloud/Audience Manager Audiences: Next Page
Analytics: up to 48hrs.
Once you upload a file in a customer attribute data source that is subscribed to Target, it can take up to 24 hours to be available. For Analytics it can take up to 12 hours.