The PHP.net site has posted an announcement about the release of the latest beta in the pre-releases of the PHP 7.2.0 series - PHP 7.2.0 Beta 2.
The PHP development team announces the immediate availability of PHP 7.2.0 Beta 2. This release is the second beta for 7.2.0. All users of PHP are encouraged to test this version carefully, and report any bugs and incompatibilities in the bug tracking system.
[...] For more information on the new features and other changes, you can read the NEWS file, or the UPGRADING file for a complete list of upgrading notes. These files can also be found in the release archive.
As always this pre-release version is available for download from the usual QA sites: source packages and Winodws binaries. The next beta will be released on August 17th and will be the final beta version before the full release.