Codedeploy from AutoScaling taking long time

Hi,

We trigger autoscaling on a TargetResponseTime threshold. Launch and turning healthy for new EC2 instance takes close to 20 mins. When we check the codedeploy we see two kinds of time, one in Deployment history start time Aug 22, 2019 3:10 PM and end time Aug 22, 2019 3:28 PM. Going to that particular deployment, we see duration as 2 minutes 21 seconds, from ApplicationStop to AfterAllowTraffic. Where is the rest of the time spent? Why is that Deployment history shows 18 mins where as the deployment time is 2 mins 21 sec?

Regards,
Santhosh I C