COVID-19 is scrambling plans all around the world, including the Googleplex. It remains to be seen how our measures for slowing the spread of this coronavirus will impact things like the development plans and release schedule for Jetpack Compose. In theory, Compose work can be done form anywhere. In practice, switching a workforce from 100% office to 100% work from home will add uncertainty at best and inefficiency at worst, as developers shift where, when, and how they are getting their work done.
There might also be knock-on effects from other slowdowns. For example, perhaps Android R will be delayed, partly due to challenges in getting the OS itself ready, but partly due to slowdowns affecting the release of next-generation Pixel hardware. Would this sort of change impact Jetpack Compose? In theory, no. In reality, this sort of stuff can get intertwined and may not be as loosely coupled as we would like.
In short, while we never really knew when Jetpack Compose might ship its first alpha, any of our previous guesses probably should be tossed out the window.