The Validity of the forecast_value in the Economic Calendar of MQL5

 
MQL5 provides functions and structures for retrieving event information from the economic calendar.

MqlCalendarEvent and MqlCalendarValue correspond to this functionality.

While implementing an EA using this feature, several questions have arisen.

How is the forecast_value included in MqlCalendarValue determined? There are cases where it clearly deviates from general forecast values.

 How much delay is there in determining the actual_value included in MqlCalendarValue after the actual indicator is released? (From what I have confirmed, there was a delay of 3 minutes and 50 seconds after the release of the U.S. employment report.)