Integration tests fail since Bamboo 7.X on license problem

I’m currently blocked on running integration tests on any 7.X version of Bamboo.

Running integration tests with “atlas-mvn integration-test” works fine for Bamboo 6.X versions. When using a 7.X version, the same integration tests fail because the server cannot be started. The test just keeps waiting for Bamboo to start:

...
[INFO] [talledLocalContainer] INFO: Server startup in 32923 ms
[INFO] [talledLocalContainer] Tomcat 8.x started on port [6990]
[INFO] Waiting for http://localhost:6990/bamboo to start
[INFO] Waiting for http://localhost:6990/bamboo to start
[INFO] Waiting for http://localhost:6990/bamboo to start
...

When browsing to http://localhost:6990/bamboo at this point, the same error message is shown as described in the KB article Unable to run pre-bootstrap upgrade tasks as your support period has ended | Bamboo | Atlassian Documentation. That is, something is wrong with the license.

It was my understanding that for development versions of Bamboo, a timebomb license was genereated at startup with a validity of 3 hours. This seems to work fine for running integration tests with 6.X versions of Bamboo, but not for 7.X. What has changed?

When looking at the license.string value in the bamboo.cfg.xml file of all 6.X and 7.X instances, the value is always the same:

<property name="license.string">AAAB1Q0ODAoPeNp1kl1v2jAYhe/9KyztDslA6OgKUqRB4q5oLIlCwrZuu3CSF/Ca2JHtsPHvZ0Kisa699Md5/Zxz/OZecRzmBk/usHM7n97Nx++wRzcJnoydW5SxKpNyuOY5CA204IZL4dIgoXEUrzYUBU2VgQp3qQal3SnypDAsNwGrwK2eSuDCvGemZFpzJoa5rPqRvXDZLtcyZ+ViD8JolzgoalR+YBp8ZsC1IFPijMlkhnqO3zVXp/Ywunnod5NTDe27Pt3SdRjRuKehnxgvX8HZgDqCWvnu8sMsIV/S7Vvy8fHxgSzHzuee1Y7gR3CNauBl/BgqaaDjn6JNk+lc8boN63VVVDLR2v035bOPKw//Hz4zORgMgjAh92FMojj0Uy9ZhQFJN9QeuJ4CG1OBsxM2B8DdFExFLgtQuFbyJ9j2vx2Mqb/PR6O9dXudz6i8KAhcFD+G2JdYSIMLro3iWWPATuYaG4nzRhtZ2Y8wRDZxYUAwkV+3ZaucEWdCbpwztRfTRUJ9svx6Jn25ng7Y9pOKJyF/CRSqPRNcszbcRX8ZtUbt1vMv0/FvLdVZMEE+/O0mAW1wdwPvpM2jbPZc4AKOUMraahA9srK5PLZjpQb0B/bqGhMwLAIULvlfGcAk9IqTtTlvDsAO/vWYtLkCFAPrevwKuxPemeMB89/CdfH4SZp/X02ma</property>

Please note that the exact same problem persists even after running altas-mvn clean or a full removal of the target/ folder.

Anyone else experiencing this?

Thank you for your help.