Notifications were failing.  We looked in the server log in debug, and found we connected the server, but were 'rejected for policy reasons'.

Iissue was From address: no-reply@skybot-scheduler-server.com

Changed it to skybot@customer_domain.com 
Their might have been some additional work that needs to be done by the smtp admin on the server side to get the skybot@customer_domain.com to work.