Following a problem introduced by Schurch [M. Schurch, , Doctoral Dissertation, University of Victoria, 2013], we find exact values of the minimum number of colours required to properly edge colour , , using natural numbers, such that the length of a shortest maximal path of increasing edge labels is equal to three. This result improves the result of Breytenbach and Mynhardt [A. Breytenbach and C. M. Mynhardt, On the -to appear-Ascent Chromatic Index of Complete Graphs, , to appear].