diff --git a/aman/config/AirportSequencing.py b/aman/config/AirportSequencing.py
index a9d285f..ddf59de 100644
--- a/aman/config/AirportSequencing.py
+++ b/aman/config/AirportSequencing.py
@@ -13,7 +13,7 @@ class AirportSequencing:
         self.ActiveArrivalRunways = []
         self.RunwayDependencies = []
         self.LastUpdateTimestamp = dt.utcfromtimestamp(int(time.time())).replace(tzinfo = pytz.UTC)
-        self.UseMustShallMay = True
+        self.UseShallShouldMay = True
 
     def clearData(self):
         self.ActiveArrivalRunways.clear()
diff --git a/app.py b/app.py
index 0b04076..3f94468 100644
--- a/app.py
+++ b/app.py
@@ -54,7 +54,7 @@ def configuration(icao):
 
     dictionary = {
         'airport' : airport.Icao,
-        'useMustShallMay' : config.UseMustShallMay,
+        'useShallShouldMay' : config.UseShallShouldMay,
         'activeRunways' : config.ActiveArrivalRunways,
         'dependentRunways' : dependencies
     }
@@ -93,15 +93,15 @@ def configure():
         return Response('{}', status=404, mimetype='application/json')
 
     # check that all top-level information are available
-    if 'useMustShallMay' not in data or 'activeRunways' not in data or 'dependentRunways' not in data:
+    if 'useShallShouldMay' not in data or 'activeRunways' not in data or 'dependentRunways' not in data:
         return Response('{}', status=404, mimetype='application/json')
-    if False == isinstance(data['useMustShallMay'], bool) or 0 == len(data['activeRunways']):
+    if False == isinstance(data['useShallShouldMay'], bool) or 0 == len(data['activeRunways']):
         return Response('{}', status=404, mimetype='application/json')
 
     # create the toplevel information
     config = AirportSequencing(airport.Icao)
     config.Airport = data['airport'].upper()
-    config.UseMustShallMay = data['useMustShallMay']
+    config.UseShallShouldMay = data['useShallShouldMay']
 
     # parse the active runways
     for activeRunway in data['activeRunways']: