On the main PHP.net site they've posted an announcement about the release of the latest alpha version of the next major PHP release: PHP 7.3.0 alpha 3.

The PHP team is glad to announce the release of the third PHP 7.3.0 version, PHP 7.3.0 Alpha 3. The rough outline of the PHP 7.3 release cycle is specified in the PHP Wiki.

[...] Please carefully test this version and report any issues found in the bug reporting system. [...] The next release would be Beta 1, planned for July 19th.

This latest release fixed bugs in a wide range of functionality all across the language including PostgreSQL handling, regular expressions, DOM parsing, the intl extension and OpenSSL. You can find complete details in the changes in the NEWS file for this latest release. As with other pre-stable releases, you can download this latest version for testing from the QA site for source packages or the Windows QA site for the Windows binaries.