The kubernetes operator docs mentions that adaptive scaling is available in 1.18 (which I believe will be released later in september). But it also says that it can be previewed with the 1.18 snapshot version. Where is this preview available?

You would have to build it yourself

Ah, ok! Thanks 🙂!

There are snapshot builds available online, you can check this example: https://github.com/apache/flink-kubernetes-operator/blob/main/examples/autoscaling/Dockerfile