'Override save to update all included tickets if Milestone.project changed'

def save(self, *args, **kwargs):

    if self.id:
        original = Milestone.objects.get(pk=self.id)
        super(Milestone, self).save(*args, **kwargs)
        if (self.project != original.project):
            for task in self.task_set.all():
                task.project = self.project
                task.save()
    else:
        super(Milestone, self).save(*args, **kwargs)
