Docker managers are losing quorum on AWS
It seems like the AutoScaling Group from AWS are not that synchronized with the Docker Swarm configuration and the default timeouts in the AutoScaling are not accepted in the Docker Swarm managers.

Actually the Health Check is not configured good by default in the EE CloudFormation template, even if the managers are running and stable the Health Check fails and the AutoScalling Group tries to launch new managers. New launched managers are not able to become cluster participants, right after their running state.