diff --git a/src/managers/AllDayManager.ts b/src/managers/AllDayManager.ts
index 17cc8b6..0fec456 100644
--- a/src/managers/AllDayManager.ts
+++ b/src/managers/AllDayManager.ts
@@ -183,45 +183,26 @@ export class AllDayManager {
 
     const allDayEvents = container.querySelectorAll('swp-event');
 
-
     // Calculate required rows - 0 if no events (will collapse)
     let maxRows = 0;
 
     if (allDayEvents.length > 0) {
-      // Expand events to all dates they span and group by date
-      const expandedEventsByDate: Record<string, string[]> = {};
-
+      // Track which rows are actually used by checking grid positions
+      const usedRows = new Set<number>();
+      
       (Array.from(allDayEvents) as HTMLElement[]).forEach((event: HTMLElement) => {
-        const startISO = event.dataset.start || '';
-        const endISO = event.dataset.end || startISO;
-        const eventId = event.dataset.eventId || '';
-
-        // Extract dates from ISO strings
-        const startDate = startISO.split('T')[0]; // YYYY-MM-DD
-        const endDate = endISO.split('T')[0]; // YYYY-MM-DD
-
-        // Loop through all dates from start to end
-        let current = new Date(startDate);
-        const end = new Date(endDate);
-
-        while (current <= end) {
-          const dateStr = current.toISOString().split('T')[0]; // YYYY-MM-DD format
-
-          if (!expandedEventsByDate[dateStr]) {
-            expandedEventsByDate[dateStr] = [];
-          }
-          expandedEventsByDate[dateStr].push(eventId);
-
-          // Move to next day
-          current.setDate(current.getDate() + 1);
-        }
+        const gridRow = parseInt(getComputedStyle(event).gridRowStart) || 1;
+        usedRows.add(gridRow);
+      });
+      
+      // Max rows = highest row number in use
+      maxRows = usedRows.size > 0 ? Math.max(...usedRows) : 0;
+      
+      console.log('🔍 AllDayManager: Height calculation', {
+        totalEvents: allDayEvents.length,
+        usedRows: Array.from(usedRows).sort(),
+        maxRows
       });
-
-      // Find max rows needed
-      maxRows = Math.max(
-        ...Object.values(expandedEventsByDate).map(ids => ids?.length || 0),
-        0
-      );
     }
 
     // Animate to required rows (0 = collapse, >0 = expand)