Merge pull request #1587 from codatio/update-read.completed.initial-description

update read.completed.initial description

Author: mattwbeard

docs/using-the-api/webhooks/migrating-to-new-event-types.md

@@ -587,7 +587,7 @@ When adopting the new schema, ensure that you handle all elements in the `dataTy
 
 Called when initial syncs are complete for all data types queued for a newly connected company, and at least one of those syncs is successful.
 
-The replacement `read.completed.initial` webhook is called the first time the data type is stored in Codat's cache and uses the same payload as the `read.completed` webhook.
+The replacement `read.completed.initial` webhook is called when data is successfully read after each time a connection is authorized. Uses the same payload as the `read.completed` webhook.
 
 :::tip Adopting the new schema
 When adopting the new schema, ensure that you handle all elements in the `dataTypes` array to maintain future compatibility.