is a source to an aws s3 bucket behind an ssh bastian supported

Hmm, I don't know enough to give you a confident answer yet. Based on the provided knowledge sources, there is no direct mention of supporting a source to an AWS S3 bucket behind an SSH bastion. For more detailed and up-to-date information, you might want to check the [Airbyte documentation](https://docs.airbyte.com/) or open a new topic on the [Airbyte community forum](https://discuss.airbyte.io/).