Bill set out around 5am from the Lhotse Face, Camp 3, (roughly 23,000 feet) and climbed past the Yellow Band, the Geneva Spur, into the death zone, to arrive at Camp 4, (approximately 26,000 feet) on the South Col. He's very tired after a long day, which as John commented is entirely normal. John further said, that in his opinion, the day that takes the climber from Camp 3 to 4 is "in many ways harder than Summit Day."
Bill's irrepressible sense of humour remains in tact, and after his rest, is in position for a planned departure from Camp 4 of around 9 PM, May 11 (local time), in order to arrive at 29,029 feet, the summit of Mt Everest, in the early morning of Thursday, May 12, 2011 (Nepal time). Hopefully, he'll even catch the sunrise with clear skies.