Bug? Hourly schedule_type runs in reverse

[thinkwelltwd]

I'm using Django Q to send emails on an hourly basis, and after the job runs, the "next_run" setting is changed to 2 hours prior to the run just complete, so the next minute the scheduler checks for new jobs if finds that same job, and reruns it, and again schedules it for 2 hours further back in history. Here's a printout taken over several job runs.

run 1. core.tasks.send_mail 2016-01-04 22:57:23.159561
run 2. core.tasks.send_mail 2016-01-04 18:57:23.159561
run 3. core.tasks.send_mail 2016-01-04 10:57:23.159561
run 4. core.tasks.send_mail 2016-01-03 02:57:23.159561
run 5. core.tasks.send_mail 2016-01-02 14:57:23.159561

And I suppose one gets the idea. If I switch the schedule_type to DAILY, then the next_run advances as expected.

Now, change schedule_type = "D":

run 1. core.tasks.send_mail D 2016-01-01 17:57:23.159561
run 2. core.tasks.send_mail D 2016-01-02 12:57:23.159561
run 3. core.tasks.send_mail D 2016-01-03 12:57:23.159561
run 4. core.tasks.send_mail D 2016-01-04 12:57:23.159561
run 5. core.tasks.send_mail D 2016-01-05 12:57:23.159561

And then by run 5 it's fully caught up and stops running every minute. Here's my code, which I'm calling in apps.py.

   class MyAppCore(AppConfig):
       name = 'core'
       verbose_name = 'MyApp Core'

    def ready(self):

        send = 'Cron: send_mail'
        if not Schedule.objects.filter(name=send).exists():
            Schedule.objects.create(
                name=send,
                func='core.tasks.send_mail',
                schedule_type=Schedule.HOURLY,
            )

The task is just a wrapper around the management command:

def send_mail():
    management.call_command('send_mail', **{'cron': 1})

[thinkwelltwd]

Ok, egg on my face. I had the TimeZone problem in my settings file. Finally found the problem after a some careful placing of print statements showed that the next_run time changed between saving & extracting from the db. TADA. Gah!

Thanks for this excellent library!