I used to brew at a pub where I couldn't pull my mash on brew days because I couldn't drag the cans through the dining room during open hours... (no accessible back door to take the cans out, stupid) To be honest, it was my idea to do it this way... previous brewers had pulled mash during the day, rolling the cans through the dining room on a handtruck and the smell from the spent-grain cans and the fact that they were pretty much always covered with bird $#!+ made some customers VERY upset while they were trying to enjoy a burger and a beer... don't blame them a bit...
SO, to avoid grossing out the customers, I had to be grossed out myself. Let it sit over night and pull it at like 7am when I came in to work. Shoveling 15 bbls worth of reeking mash was MOST unpleasant, I can assure you... especially since (due to another STUPID design at this place) the grain had to be shoveled onto the floor first, and then into a can... In the words of Dr. Suess; STINK, STANK, STUNK
I discovered that a cold water sparge (draining to the floor drain of course) after I had completed my runoff helped the situation. Rapidly dropping the temp of the mash slowed the souring process dramatically. It was still unpleasant, but nowhere near as bad as it had been!
I worked at three breweries owned by this same company and all three of them had at least one STUUUUPID design flaw that made it really hard on the brewer. Morons LOL