11 o'clock the next morning!
He left for work at 10am on Monday and got back at 11am on Tuesday. What happened was something technical which I didn't quite understand - but it was an urgent job, and there wasn't anyone else around who could fix it. Since their engineer left, Richard's now the only person in the company with a clue about technical stuff. The company badly needs to get a new engineer - and it has to be someone competent, as an incompetent engineer is worse than none at all.
In other news, I am very amused by this livejournal entry in bethdeth's journal.