It's table format version 2. I have tried using a different catalog name but this just doesn't seem to work in a workspace with unity catalog enabled, only spark_catalog works. We are starting to think we've made a mistake creating our workspace with unity catalog enabled as we cannot access any of the iceberg metadata or procedures using four part naming.

I have created a test workspace without unity catalog and tried an update on a different table. Here we can use anything we choose as the catalog name. However we still see the iceberg-version=unspecified.