Thank you for contacting Syncfusion Support.
"Automatic Refresh" option normally gets the updated data from target SQL Server to the dashboard and it will not directly contact web data source. Our Data Agent Tool only extracts the updated data from web data source and pushes it to the target SQL Server based on scheduled refresh. If the target SQL Server gets the updated data before triggering auto refresh option, then the dashboard will get the updated data.
Please let us know if you need any further assistance on this.