It's been almost four weeks since Google released Android P developer preview 3, complete with final APIs. Today, the company announced the fourth developer preview, or the third beta. According to the program overview, this is indeed a release candidate. There should be another release candidate later on this month, followed by the final release later this quarter.
That also means that if you're a developer, you can now submit apps that are targeted at Android P (API level 28) to the Google Play Store. Those running the beta will get the app update, so the app will be tested on a variety of beta hardware.
With Project Treble, the Android beta program is available on more devices than in previous years. You can currently install it on the Essential Phone, Google's Pixel family of phones, Nokia 7 Plus, OnePlus 6, Oppo R15 Pro, Sony Xperia XZ2, Vivo X21UD, Vivo X21, and Xiaomi Mi Mix 2S.
There aren't any new features in today's build, as it's really all about refining it so that it's polished enough to be considered a release candidate and a near-final system image. However, there is an update to Android Studio, including D8 as an independent tool.
Google still hasn't announced what the name of Android P will be, and it seems likely that the company will unveil it soon. It's also worth considering that with the final developer preview slated to launch later this month, the final build could arrive as soon as next month.