Based on the provided knowledge sources, there is no explicit information about the specific HTTP method used for webhook notifications in Airbyte. The documents mainly focus on how to set up and configure webhook notifications, but they don't mention the HTTP method used to send these notifications. However, it's worth noting that webhooks typically use the POST method to send data to the specified URL. While this is a common practice, I cannot definitively state that Airbyte uses POST for its webhook notifications without explicit confirmation from the provided documentation. If you need to know the exact HTTP method used for Airbyte's webhook notifications, I recommend checking the official Airbyte documentation or contacting their support team for more detailed technical information.