The Bitbucket Server 4.0.2 Linux .bin installer bundles JRE 1.8.0_60, however after installation completes the installer tries to start the instance using what is defined as JAVA_HOME. If JAVA_HOME is pointing to Java 1.7 the instance won't start because Java 1.8 is required.

There's no point in packaging the required JRE if it's not used.
Maybe the startup process could check if JAVA_HOME is pointing to 1.7 and:

• If it is pointing to Java 1.7, use the JRE_HOME included in the package.
• If it is pointing to Java 1.8, use JAVA_HOME.