They don't look at your usage at all. You can stop using for a month and it won't affect your shaping. They look at overall network stress in your area.
If your are routing through Cape Town, the shaping will only be lifted in the early morning hours.
Till the new capacity is added, we will stay in this semi permanent shaping state unfortunately.
The north of South Africa also has aggressive shaping. I've been shaped what feels like 24/7 (I go to bed at 12, so shaping probably eases up at 1am as well). The worst part is that we have additional IPC, yet we're back to square one. I don't think additional IPC will cure all of the uncapped issues