Thanks for your reply dot-mike, I'm sure you're attempting to be helpful with your message. However, as I mentioned in my original post I'm running Elasticsearch on a separate cluster not in docker, hence my being able to upgrade the Elasticsearch cluster with apt to version 8.18.2
The docker command you're referencing there is for downloading the Elasticsearch image. In that article you've helpfully posted though, it does reference also downloading the Kibana image, which I've also explained in my original post, is what I was trying to do; I've tried pulling the 9.0.2 image and the 8.18.2 image, using the docker command
docker pull docker.elastic.co/kibana/kibana:8.18.2
But seemingly regardless of which image I pull, Kibana seems to think it's running on version 8.12.0. In case docker might have been getting confused with there being multiple images downloaded, I purged all the Kibana images from all three nodes in my docker swarm with this command
docker image rm [image id]
after which I've tried manually pre-downloading the Kibana image, and also getting the docker compose process to do the image download as part of provisioning the service.
I am using the docker compose project, and I have used the kibana/kibana:8.18.2 image reference in the compose yaml, as it's Kibana that I want to run, not Elasticsearch.
I think I can say that I have a fair bit of experience with docker now, and this is why it's confusing. Despite that new image entry being in my compose file, and a seemingly new Kibana image being downloaded, the version in Kibana when it is available again after loading, seems to always be 8.12.0
Any ideas relating to that issue would be very gratefully received.