We can see updates to deployment using command:
kubectl rollout history deploy/<name>
We can also see updated config using:
kubectl rollout history --revision=<revision-#> deploy/<name>
I'm not sure how to find out given revision's update time. Is it possible to find it?
If you are storing events from the namespace or api server logs, you might be able to find out. One crude way will be to look at creation time for replica sets of the deployment - kubectl get replicaset