15 seconds difference on a time of 225 seconds [3:45 avg MAP time] is ~7% which is not a huge difference - especially if the testing was not particularly well controlled for other factors.

If the test bike had some known issues with the suspension it seems kind of pointless [beyond filling a few pages] to test it in the first place until those problems were resolved.

Although Jan would certainly print any additional material in subsequent issues the fact is many people who read that first article will not see the correction/addendum.