[ Ok, I've rebuilt the RC - and it contains only the changes to function and MPL ]

The release candidates for the third 1.69.0 beta release are now available at:
<https://dl.bintray.com/boostorg/beta/1.69.0.beta1.rc3/source/>

The release notes are not yet final.

The SHA256 checksums are as follows:
ee0ecd7d31f58474c1e0210089c9e66bd878d4d1e7436ac511e359aa4a9d3e86  ./boost_1_69_0_b1_rc3.7z
3e25c46f2171799caabbeb419ba7859fffb62208f3a1c80798713377ab07af0e  ./boost_1_69_0_b1_rc3.tar.bz2
71f4b57175058af1b8c320971cf29226e5a652931a679f7e1c086655147ecafb  ./boost_1_69_0_b1_rc3.tar.gz
ec9ef7d2c9f0d41f560769e67bc7ff207cc999243a7dd6c3f6bcfbdbf0827a7b  ./boost_1_69_0_b1_rc3.zip

As always, the release managers would appreciate it if you download
the candidate of your choice and give building it a try. Please report
both success and failure, and anything else that is noteworthy.

-- The Boost Release Managers