fix: add slm start time grace_minutes=15 grace period to include data starting at start time.

backend/routers/projects.py

@@ -119,10 +119,18 @@ def _filter_rnd_rows(
     filter_start_date: str,
     filter_end_date: str,
 ) -> list[dict]:
-    """Filter RND data rows by time window and/or date range. Handles overnight ranges."""
+    """Filter RND data rows by time window and/or date range. Handles overnight ranges.
+
+    Grace window: intervals starting up to 15 minutes before the filter start time are
+    included. This covers the common case where a unit is deployed slightly early
+    (e.g. set up at 6:50 for a 7:00 PM start) and the first interval begins just before
+    the nominal window. The grace window applies only to the start boundary.
+    """
     if not filter_start_time and not filter_end_time and not filter_start_date and not filter_end_date:
         return rows
 
+    _GRACE_MINUTES = 15
+
     filtered = []
 
     start_hour = start_minute = end_hour = end_minute = None
@@ -174,14 +182,23 @@ def _filter_rnd_rows(
                 row_time_minutes = row_hour * 60 + row_minute
                 start_time_minutes = start_hour * 60 + start_minute
                 end_time_minutes = end_hour * 60 + end_minute
+                # Effective start allows up to 15 min early (wraps midnight correctly)
+                effective_start = (start_time_minutes - _GRACE_MINUTES) % (24 * 60)
 
                 if start_time_minutes > end_time_minutes:
                     # Overnight range (e.g., 19:00-07:00)
-                    if not (row_time_minutes >= start_time_minutes or row_time_minutes < end_time_minutes):
+                    # With grace: effective start may be e.g. 18:45
+                    if effective_start > end_time_minutes:
+                        # Grace window doesn't wrap past midnight itself
+                        in_window = (row_time_minutes >= effective_start or row_time_minutes < end_time_minutes)
+                    else:
+                        # Grace window wraps midnight (rare: start near 00:00)
+                        in_window = (row_time_minutes >= effective_start and row_time_minutes < end_time_minutes)
+                    if not in_window:
                         continue
                 else:
                     # Same-day range (e.g., 07:00-19:00)
-                    if not (start_time_minutes <= row_time_minutes < end_time_minutes):
+                    if not (effective_start <= row_time_minutes < end_time_minutes):
                         continue
 
             filtered.append(row)