This must have happened at night. I operate in/out of JNB quite often, the taxiways are poorly lit and not marked all that well, like we are used to in the States and Europe. It's much worse when it's dark and raining but I think it was clear that night.

I don't ever recall seeing that building down there but I was never on the wrong taxiway (yet), or gone past the turnoff for 3L. I'm going there a few days after Christmas, I'll have to ask for taxiway Mike so I can get a real good look at the newly configured building!
Should be plenty of wingtip clearance now, right?