When the container starts, it shows the following config values having been read:

'STATS_CALCULATION_INTERVAL': 7,
'STATS_CALCULATION_LOGIN_TIME': 30,
'STATS_ENTITY_LIMIT': 100,

Yet, when the cron job runs, it loops with:

2018-01-30 16:50:17,561 - ERROR - Going to sleep for 3 seconds and then try again...
2018-01-30 16:50:17,561 ERROR Going to sleep for 3 seconds and then try again...
2018-01-30 16:50:20,567 - ERROR - Error while getting user list for stats calculation: module 'listenbrainz.custom_config' has no attribute 'STATS_CALCULATION_LOGIN_TIME'

And that config value really does seem to come from custom_config.py