I am behind the Riebeek Kasteel town square, on the Wellington side. Hence, in a slight dip. We drove right around the Kasteelberg Mountain and as soon as I headed towards Riebeek West one of the local masts came into view and bingo - there was rain. Data transfer was good. We lost it of course on the other side of the mountain and it re-appeared at the top of the Bothmaskloof Pass as we completed the circle. Arriving back home, I discovered that I can JUST get 25% if I step outside the back door, and hold it high. I'm in the house now, and I see zilch.
I also tracked the signal all the way to Malmesbury and on to Cape Town. Nothing at first, but At Malmesbury the signal came on strong, and google maps kept us up to date all the way down the N7 into town. HOWEVER, even in the CBD the signal seemed erratic. I will do more tracking soon, I just got a new P20 (Lite), I've put the SIM in there, and that gets me right up to date on the device side (doesn't it?)

Andy