hmm, maybe if your extension has functionality that is only available when the stream is live.
My panel-extension got released without me being live. The only thing I needed to do was actually create a test-clip on my channel, as this is the main feature of my extension.
If your extension requires a live stream, maybe you can find an actual streamer who would like to test your extension. Then you can add them as Testing Accounts in the extension’s “Access” tab.
Or provide Twitch with a time-frame when your stream will be live (just make sure it’s during business hours in San Francisco).