strange, but I actually get lower rates with 1.2 on RX480 8G with Uber 3.1 mem timings
(running with  -g 2 -w 64 -X 256 --benchmark)

X16r    Avermore-1.1    8.4 mh
X16r    Avermore-1.2    7.743 mh

X16s    Avermore-1.1    8.366 mh
X16s    Avermore-1.2    7.711 mh