Based on the available knowledge sources, Elementary does support dbt-core v1.9, as confirmed by a trusted support staff member: "For sure!" when asked about compatibility with dbt-core v1.9 [Slack thread](https://slack.com/archives/C02CTC89LAX/p1734962345464009). However, there is no explicit information in the knowledge sources about Elementary's compatibility with dbt 1.9.5 specifically regarding the removal of the data-tests explicit override flag. The documentation and support threads discuss the need for the

require_explicit_package_overrides_for_builtin_materializations: false

flag for dbt 1.8.x, but do not mention changes in dbt 1.9.5 or how Elementary handles the removal of this flag. Therefore, while Elementary is compatible with dbt-core v1.9 in general, the knowledge sources do not provide enough information to confirm compatibility with dbt 1.9.5 in the context of the override flag removal. If you are relying on features that require overriding materializations, you may want to proceed with caution and consult the latest Elementary documentation or support channels for updates on dbt 1.9.5 support.