When will TestFlight start supporting App Clips?

I'm building an app clip and I'm trying to create an invocation experience in Testflight so that I can create a demo for one of our customers.

Is there an estimated date that Testflight will start supporting app clips? Because the invocation is not really testable from an url using the current local development flow, because this flow is only a small part of the full experience.

Thanks in advance!