Merge pull request #6588 from segmentio/do-data-freshness

Add q about data freshness to Delivery Overview docs

Author: forstisabella

src/connections/delivery-overview.md

@@ -102,6 +102,8 @@ Connections Alerting allows you to create two different alerts:
 - **Source volume alerts**: These alerts notify you if your source ingests an abnormally small or large amount of data. For example, if you set a change percentage of 4%, you would be notified when your source ingests less than 96% or more than 104% of the typical event volume.
 - **Successful delivery rate alerts**: These alerts notify you if your destination's successful delivery rate falls outside of a percentage that you set. For example, if you set a percentage of 99%, you would be notified if you destination had a successful delivery rate of 98% or below.
 
+## How "fresh" is the data in Delivery Overview?
+The data in Delivery Overview has an expected latency of approximately 30 seconds after event ingestion, but this may vary, depending on the features you’ve enabled in your workspace and spikes in volume. Segment delays the data visible in the Delivery Overview UI by 5 minutes to allow for more precise metric correlation. Segment does not impose the 5 minute delay if you access data using the Public API.
 
 ## Why is the Delivery Overview page only available for cloud-mode destinations? 
 Similar to Segment's [Event Delivery](/docs/connections/event-delivery/) feature, the Delivery Overview page is only available for server-side integrations (also known as cloud-mode destinations). You won't be able to use the Delivery Overview page for client side integrations (also known as device-mode destinations) because device-mode data is sent directly to the destination tool's API. In order to report on deliverability, data must be sent to destinations using a server-side connection.