Milestone 13 was completed on 2020-07-04. It adds support for building the foxy 2020-06-25 release with all of the OpenEmbedded release series and webOS OSE. It also adds support for building all of the ROS distros (including foxy) with OpenEmbedded gatesgarth (the next release series, currently in active development).
A new revision 20 of the OpenEmbedded Build Instructions updated for this has been published. Its change log is here. A “rich diff” of the changes made since the previous revision is here.