What happened to the 2.9 branch?

For a client I had been using version 2.9.4 of the plug-in. When I re-ran the build script for their staging site, it errored because it could not longer find version 2.9.4.

It was no big issue, we simply updated to 2.10.0 – but I just wondered, what happened to the 2.9 branch. Was it removed accidentally, or was there a reason for its removal?

Thanks,
Stephen