I tested with several other versions and got the following weirdly unpredictable behaviour:
(django_1.7) $ for _ in {{1..10}}; do ./manage.py makemigrations; done
Migrations for 'app1':
0003_auto_20160929_2012.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0004_auto_20160929_2012.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0005_auto_20160929_2012.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0006_auto_20160929_2012.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0007_auto_20160929_2012.py:
- Alter field fk_to_model1 on model2
No changes detected
Migrations for 'app1':
0008_auto_20160929_2012.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0009_auto_20160929_2012.py:
- Alter field fk_to_model1 on model2
No changes detected
No changes detected
(django_1.8)$ for _ in {{1..20}}; do ./manage.py makemigrations; done
No changes detected
No changes detected
Migrations for 'app1':
0003_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0004_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
No changes detected
Migrations for 'app1':
0005_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
No changes detected
No changes detected
Migrations for 'app1':
0006_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0007_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0008_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
No changes detected
Migrations for 'app1':
0009_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
No changes detected
No changes detected
No changes detected
Migrations for 'app1':
0010_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
No changes detected
No changes detected
Migrations for 'app1':
0011_auto_20160929_1957.py:
- Alter field fk_to_model1 on model2
(django_1.9)$ for _ in {{1..10}}; do ./manage.py makemigrations; done
Migrations for 'app1':
0003_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0004_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0005_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0006_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0007_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0008_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0009_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0010_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0011_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2
Migrations for 'app1':
0012_auto_20160929_2010.py:
- Alter field fk_to_model1 on model2