diff --git a/src/MissionManager/CorridorScanComplexItem.cc b/src/MissionManager/CorridorScanComplexItem.cc
index c6a8a787c2f68c50a07c0f5196beaf7e33a0080b..bcb69fc213fba4586c57879635b988e3512bea50 100644
--- a/src/MissionManager/CorridorScanComplexItem.cc
+++ b/src/MissionManager/CorridorScanComplexItem.cc
@@ -69,7 +69,7 @@ int CorridorScanComplexItem::lastSequenceNumber(void) const
         itemCount += _transectCount() * 2;
     }
 
-    return _sequenceNumber + itemCount - 1;
+    return _sequenceNumber + itemCount;
 }
 
 void CorridorScanComplexItem::save(QJsonArray&  missionItems)