Sonarqube 6.7.1 - Community Edition - License upgrade to Developer edition, service wont start

We applied a development license to our on prem community instance of Sonarqube (6.7.1) and after the license was applied and updated, i restarted sonar.
The application will not come back up, the service starts and terminates immediately.
There were a few elastisearch issues that were identified and resolved, but we are still getting:

2019.09.03 13:58:54 WARN app[][o.s.a.p.AbstractProcessMonitor] Process exited with exit value [es]: 143

The site will not come back up, we get the following error:
Service Unavailable

The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.

We cant understand how applying a license has bricked the system. We didnt specify that we wanted to upgrade to a new version when we applied the license.

Logs available on request to Sonar support Engineers.

Hi,

Welcome to the community!

What shows up in your other logs?

 
Ann