celerybeat uses UTC even with timezone settings

Turns out that it was a bug in celery which is now fixed. See https://github.com/celery/django-celery/issues/150

I think that you want

CELERY_ENABLE_UTC = False

The celery configuration docs state pretty clearly that if this value is true, dates and times are converted to UTC. Also note this value is enabled by default since version 3.0.