Starting to look like I have double thickness plasterboard at 16mm each so the hollow wall anchors are probably out.
So with those framing screws is it just a plastic rawlplug in whatever it is behind the boards then just screw the bracket up to the face of the board? Wouldn't it pull the board...
Interesting... The brackets on mine take an M6 screw max so would be the 20mm version, 20mm is a very big hole though. Stocked in wickes and screwfix so might pick some up tomorrow
Hoping you're still watching this topic mdproctor as I am in exactly the same situation, dot and dab insulated plasterboard, 70mm from surface to brick using the exact same mount as you (IBRA version from amazon)
TV is also just under 20kg, was going to use M5 intersects similar to these...