After the renovation of the course, has the start/finish been in the exact same place? Is the course run the exact same way? The point is, measurements are made much more accurate now. Perhaps the course was more harsh in the past, but they run a slightly longer distance now.
At the same time, that old course does not look that bad. The surface is still hard. So you have to avoid a few rocks/roots, but come on, XC is not supposed to be on groomed golf courses!
23:48 is still incredible when put in a historical perspective. A great run, a great show of confidence!