Most of my work is quite straight forward in terms of PP, most of the work happens before I release the shutter, so that the client usually gets the first proof within 3 days. And it would be faster if the printing lab was closer.
But I delivered a photo (an image, really) today that took close to 25 hours of PP and of course, we had other things to do at the same time, so that PP was done over the course of 2 weeks.
A friend of mine takes a few months just creating one photo
Sports events where over 3000 images are involved, 7 to 10 days, but I also spend time during the event working on the images. If the client needs any images for media/website use, I send them out within an hour. Anything under 150 images, next day.