add option of limiting days back in

src/database.py

@@ -206,7 +206,7 @@ def get_latest_forecast_values_for_a_specific_gsp_from_database(
     :return: list of latest forecat values
     """
 
-    start_datetime = get_start_datetime(start_datetime=start_datetime_utc)
+    start_datetime = get_start_datetime(start_datetime=start_datetime_utc, days=365)
 
     if (forecast_horizon_minutes is None) and (creation_utc_limit is None):
         forecast_values = get_forecast_values_latest(

src/utils.py

@@ -76,7 +76,9 @@ def format_datetime(datetime_str: str = None):
 
 
 def get_start_datetime(
-    n_history_days: Optional[Union[str, int]] = None, start_datetime: Optional[datetime] = None
+    n_history_days: Optional[Union[str, int]] = None,
+    start_datetime: Optional[datetime] = None,
+    days: Optional[int] = 3,
 ) -> datetime:
     """
     Get the start datetime for the query
@@ -88,12 +90,13 @@ def get_start_datetime(
     :param start_datetime: optional start datetime for the query.
      If not set, after now, or set to over three days ago
      defaults to N_HISTORY_DAYS env var, which defaults to yesterday.
+    :param days: number of days limit the data by
     :return: start datetime
     """
 
     now = datetime.now(tz=utc)
 
-    if start_datetime is None:
+    if start_datetime is None or now - start_datetime > timedelta(days=days):
         if n_history_days is None:
             n_history_days = os.getenv("N_HISTORY_DAYS", "yesterday")