diff --git a/SAS/TMSS/src/tmss/tmssapp/migrations/0001_initial.py b/SAS/TMSS/src/tmss/tmssapp/migrations/0001_initial.py
index 9b01a3da93f1916f9119ea7781fe847fe3644db6..fedf0592a12c0a923ea386b93e7d2b3eb1e2daa5 100644
--- a/SAS/TMSS/src/tmss/tmssapp/migrations/0001_initial.py
+++ b/SAS/TMSS/src/tmss/tmssapp/migrations/0001_initial.py
@@ -1,4 +1,4 @@
-# Generated by Django 3.0.6 on 2020-07-14 21:21
+# Generated by Django 3.0.6 on 2020-07-14 21:50
 
 from django.conf import settings
 import django.contrib.postgres.fields
@@ -1019,7 +1019,7 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='project',
             name='cycles',
-            field=models.ManyToManyField(help_text='Cycles to which this project belongs (NULLable).', related_name='projects', to='tmssapp.Cycle'),
+            field=models.ManyToManyField(blank=True, help_text='Cycles to which this project belongs (NULLable).', related_name='projects', to='tmssapp.Cycle'),
         ),
         migrations.AddField(
             model_name='project',
diff --git a/SAS/TMSS/src/tmss/tmssapp/models/specification.py b/SAS/TMSS/src/tmss/tmssapp/models/specification.py
index d5a83d8971087fc970af8bd925dd5403840fc642..34b5b981e3fadfd750539d8e314af31a0978cc38 100644
--- a/SAS/TMSS/src/tmss/tmssapp/models/specification.py
+++ b/SAS/TMSS/src/tmss/tmssapp/models/specification.py
@@ -276,7 +276,7 @@ class Cycle(NamedCommonPK):
 
 
 class Project(NamedCommonPK):
-    cycles = ManyToManyField('Cycle', related_name='projects', help_text='Cycles to which this project belongs (NULLable).')
+    cycles = ManyToManyField('Cycle', blank=True, related_name='projects', help_text='Cycles to which this project belongs (NULLable).')
     priority_rank = FloatField(null=False, help_text='Priority of this project w.r.t. other projects. Projects can interrupt observations of lower-priority projects.') # todo: add if needed: validators=[MinValueValidator(0.0), MaxValueValidator(1.0)]
     trigger_priority = IntegerField(default=1000, help_text='Priority of this project w.r.t. triggers.') # todo: verify meaning and add to help_text: "Triggers with higher priority than this threshold can interrupt observations of projects."
     can_trigger = BooleanField(default=False, help_text='True if this project is allowed to supply observation requests on the fly, possibly interrupting currently running observations (responsive telescope).')
diff --git a/SAS/TMSS/test/tmss_test_data_rest.py b/SAS/TMSS/test/tmss_test_data_rest.py
index ada401713f68345bfd3bbf9374f62c6ecc7e2a84..5e83ad35086a6226a135c5facfb0b2a2145d3fa9 100644
--- a/SAS/TMSS/test/tmss_test_data_rest.py
+++ b/SAS/TMSS/test/tmss_test_data_rest.py
@@ -141,7 +141,8 @@ class TMSSRESTTestDataCreator():
                 "priority_rank": 1.0,
                 "trigger_priority": 1000,
                 "can_trigger": False,
-                "private_data": True}
+                "private_data": True,
+                "cycles": []}
 
     def ResourceUnit(self):
             return  {