That is exactly the point - there has not been anything for SV hunters. BM and MM get updates on the PTR. BM even has a mechanics overhaul, thought a minor one, not just any number tuning. We get rumors and hints about these updates way in advance. The BM changes were hinted to us almost 4 months ago, when developers were testing legendary shoulders on the PTR. Yet survival is like surrounded by vacuum. Yes, it gets numbers tuning from time to time to keep it "competitive", in theory at least. But mechanically it is such a mess, even a 10-20% dps advantage does not make people play it more often. If there was anything at all planned for SV, I bet we would know about it by now.
On a side note, when was the time anyone saw a SV hunter in a raid? I am not even sure if I met one this calendar year.