GrowthBook 1.9 introduces several major updates aimed at enhancing user experience and functionality, including the addition of a Frequentist statistics engine, the GrowthBook Proxy server, scheduled feature flags, and event-based webhooks. Users can now select between Frequentist and Bayesian statistics for experiment analysis, with future updates planned to enhance the Frequentist engine further. The GrowthBook Proxy server improves speed, scalability, and security for real-time feature rollouts and is complemented by enhancements to the Javascript and React SDKs. Scheduled feature flags allow for timed activation or deactivation of features, available in Pro and Enterprise plans, eliminating the need for manual adjustments at inconvenient times. Event-based webhooks facilitate broader integration with tools like Slack and Jira, enabling the creation of complex workflows and automation. Additional improvements include customizable metrics per experiment, project-specific metrics and data sources, and easier duplication of features, alongside numerous other changes and bug fixes detailed in the release notes.