Anything before the first JUCE 8 commit is covered by the JUCE 7 license.
If you’re in doubt, check the license headers in the JUCE version that you’re using.
juce_audio_plugin_client.h @ 16dac4a, uses JUCE 7 license, links to the juce-7-licence page (if you scroll down a bit in the file, you’ll see that the ‘version’ field inside the JUCE module declaration is 7.0.12).
juce_audio_plugin_client.h @ 2fc069b, uses JUCE 8 license, links to the juce-8-licence page, has a module version of 8.0.0.
Another place to check is the definition of JUCE_MAJOR_VERSION in juce_StandardHeader.h. If the MAJOR_VERSION is 7, you need to follow the licensing rules for JUCE 7. if the MAJOR_VERSION is 8, you need to follow the licensing rules for JUCE 8.
