This week's Week in Review mentioned that the April car pack will be released on April 10, a week later than the typical "first Tuesday of the month" schedule. As usual, the release will also come with an update to the game, meaning bug fixes, new features, etc. An earlier version of the Week in Review accidentally revealed one of the cars in the pack, as it provided details on the April car pack rivals event. So, we know that we're getting the 1985 Nissan #83 Electramotive Engineering GTP ZX-Turbo.
I'll be back with another update once we know the rest of the cars in the pack, probably with a release video as well. Stay tuned!