Error Fetching HTTP headers - iATS Recurring contribution
Sorry - we've not seen this (yet) - best to post an issue on our GitHub queue: https://github.com/iATSPayments/com.iatspayments.civicrm - so that both Alan and myself as well as iATS staff sees this. 

Perhaps the automatic ones are not run as -u your webuser but as another user - different env - different drush? 

My favourite/most stable/like clockwork (no drift) way to run the recurring contributions job is:

to switch it OFF in the scheduled jobs GUI

and then to:


  apache crontab for drupal/civicrm:
  
  0 2 * * * /usr/bin/php /usr/local/bin/drush.php --root='/var/www/platform/site/' --uri='https://site.org' -u 1 civicrm-api job.iatsrecurringcontributions auth=0 -y
  
  and then run the scheduled jobs that are switched ON:
  
  3 * * * * /usr/bin/php /usr/local/bin/drush.php --root='/var/www/platform/site/' --uri='https://site.org' -u 1 civicrm-api job.execute auth=0 -y