The "Filtered Vector Search" feature in Azure Cosmos DB for MongoDB vCore is still in preview, with no specific public announcement regarding its General Availability (GA) date available.
For the most current updates or specific timelines about the GA of Filtered Vector Search, I recommend keeping an eye on the official Azure Cosmos DB blog (Microsoft Developer Blogs) and Azure Cosmos DB documentation (MS Learn).
These sources are frequently updated with the latest information on new features, enhancements, and availability statuses for Azure Cosmos DB capabilities.