I know, and others know there are some known issues on the build with regards to 5Ghz for https://openwrt.org/toh/hwdata/tp-link/tp-link_archer_c6_v2_us .
But as I see it I and others want to use it, knowing those open issues.
Further, the snapshot builds do not contain the GUI - which is problematic for some of us to test.
Please advise what is needed to allow this to merge.
TP-Link Archer C6 v2 support has been merged into master (~= snapshots) about a year ago already, from which the next major stable release branch (20.xy) will be cut. You're probably asking for it being backported to the 19.07.x branch - that is not going to happen. Device support is usually not getting backported to existing stable branches, newly added devices will only become available in the next stable release (20.xy.0, not 19.07.z).
Exceptions to this rule of thumb exist, but they are relatively rare and shouldn't be expected to set precedence.
What you say makes sense, but begs the question what is the eta for the next release (20.x)?
According to the release schedule (https://openwrt.org/releases/start) it will be "from time to time".
If this is going to be a while (e.g. months) - what can be done to encourage such back port?
waiting for a stable build. snapsot build also have internet led problems, though its not a major problem..
We are setting up a Jenkins CI to build test configurations as discussed in https://github.com/openwrt/openwrt/pull/2470#issuecomment-729310480