Don't get me started ....
But you have.
I also have experienced this problem with VS 787. JNB is a regular port of call for me and I, too, like to see the African night and dawn. With conventional blinds, I pull a blanket over my head and cover the window, as I ease the blind up just enough. I put on my sunglasses to watch the dawn. I do not disturb anyone.
The clever boys and girls at VS don't trust me to do this so they lock all the windows. They then display a vile pink led 'sunrise' at the time they want us to wake up. Obviously the led light scheme was thought up by more clever marketing boys and girls in America. The CC say 'you can look through the porthole in the door'. Oh, really? Get up and walk to the door and peak through a tiny window every ten minutes? Great idea. As I have been travelling this route for 58 years, I think I know how to open a blind without disturbing other pax.
When they introduced the 350, we were promised it on the JNB run and the 787 would do CPT. Whenever we are travelling (and use VS) it's always the wretched 787. We are booked on them later this year for the simple reason that we have accrued a lot of points for the upgrade.
If I could, I would avoid the 787 and never travel on it again. I have found the aircraft utterly unremarkable in all aspects. Why folks say it is wonderful - I do not know. The higher cabin pressure has never made any difference to me. I can only presume that the reason we do not get the 350 as promised, is that Delta want the shiny capacity across the pond to feed their network. CPT is now southern summer only and a daylight return flight as it is a tourist route. VS has been pruned right back. I much prefer the 380 to JNB.