There are two ways to remedy the situation.
Then scale up and down. This by default will spawn a new container instance with the updated AMI. Scaling down should kill the old one.
ecs-cli scale --size 4 --capability-iam ecs-cli scale --size 2 --capability-iam
This will address issues like https://alas.aws.amazon.com/ALAS-2017-783.html.
Do it through the AWS Web console:
Devops at Spuul. Any tips or suggestions? Reach out!