python manage.py squashmigrations <appname> <squashfrom> <squashto>
python manage.py help squashmigrations
https://docs.djangoproject.com/en/dev/topics/migrations/#migration-squashing
This will give you more granular control over which migrations to squash, and let you keep a cleaner commit history. Deleting + recreating all migrations may cause other issues such as circular dependencies depending on how models are constructed.