Hello,
I am considering to release Kamailio v5.1.7 later this week, likely on Thursday, January 31, 2019.
As usual, here come the notice to report any issue that you are aware of and not yet registered on the bug tracker in order to give them a chance to be analyzed and eventually fixed before the release. Also, take a look at the branch 5.1 in git and check if there are any missing commits from those you expected to be backported.
Cheers, Daniel