I have discovered a bug in the dataset_upload form. On the first page when validating the dataset with the compliance checker, the redirect back to the start page fails when one of the compliance checker tests fails.
If compliance checker tests are both successful then the form manage to redirect correctly to the next step.
This can have been a new bug introduced in Drupal 10.2
https://www.drupal.org/project/drupal/issues/3409752
I will investigate more when I am back from holidays