User & System Administrator Forum for general questions and discussions among people using the software, including system administrators as well as end-user engineers and scientists
Developer Forum for technical discussions among developers, generally people enhancing or debugging at the source code level
webmaster@pbspro.org for feedback about the infrastructure supporting the project itself, e.g., issues or suggestions for any of the project sites: pbspro.org, pbspro.atlassian.net, community.pbspro.org, github.com/PBSPro, etc..