Opensearch version 2.11 is now available in EU-NL and can be used with new CSS instances.
Please kindly visit Opensearch Release Notes for Version 2.11 to get more information about functionalities.
Before you start the deployment of OpenSearch 2.11 please verify if you already have in the IAM Agency called css_obs_agency the OBS Administrator permission as follow:
1) Open IAM Services -> Agencies and search for css_obs_agency