The 1.52.0 pre-release is ready for testing. The release is scheduled for this Thursday, May 6th. Release notes can be found here.

You can try it out locally by running:

RUSTUP_DIST_SERVER=https://dev-static.rust-lang.org rustup update stable

The index is https://dev-static.rust-lang.org/dist/2021-05-04/index.html. You can leave feedback on the internals thread.