Last night, I finished the last major feature in the Weather Now upgrade that I started in earnest back in October 2020. That means the development app can do most of what the version 4 can do, except better in most cases. By extension, that means I just have a few things to do in order to replace version 4 in production. But "a few things" includes setting up all the production assets for the new version, including the DevOps pipelines. That's not a small job.
That last bit may take a while. I'll have more extensive release notes closer to launch. The Search feature will have the most limitations immediately post-launch as it requires replacing the current 7.5-million-row gazetteer from the external sources, rather than simply porting the data. A few other things (full internationalization, configuring your language and measurement systems, and historical data) will also take time. Modernizing the deployment pipeline makes adding these features back in a lot easier, though.
For now, the development app has weather archives back to last May and much simpler methods of accessing data than v4. I encourage you to try it out.