Revert Pi running Screenly to older version of software

Hi. I have a test RasPi on hand running a newer version of the Screenly software. What I need to do is to either revert or re-install the Screenly software to match the RasPi’s I currently have installed in production, which appear to be running an earlier version of the software. I have accessed one of these production RasPi’s (3B+) via the web interface, it states that it is currently running software version “development@d57a4d1.” I cannot find a reference on GitHub for this version.

What would be the best method for me to locate this version of the software, and to install it on the test RasPi?