It´s a good thing that I included two spare days, because otherwise we wouldn´t have made it.
All went well at first. We would climb along the normal route, ascending the plateau from the east. On the third day we reached high camp, at around 5750m or so, just below the 180m steep section. Next day, June 2, we had our first go, but various factors, the main one being the deep sugary snow on the summit plateau, stopped us short of the summit - even though we had snow shoes. After rappelling the steep section in the dark, we finally got back to high camp almost 4 hours after sunset.
Next day, I mostly rested, but our porter made a foray to base camp to get more supplies, and our guide went up the steep slope to collect a lot of gear that we had spread all over it the previous day, and also to prepare all the belay stations for our second (and final) attempt. Great!
The 4th, we started an hour earlier than before, and although it looked like we wouldn´t make it, we finally did reach the summit and even managed to get back to high camp in the twilight after sunset. I was dead beat. Only the next day the euphoria of a successful climb set in, and I felt like a million bucks :).