I'm not great with PROC GLIMMIX. Someone like @SteveDenham is probably a better choice. I assume you've read the doc for the LINES option.   If you do not use the ADJUST= option, you get all pairwise least squares mean differences and their significance. The unadjusted p-values are from a statistic that is assumed to have a t distribution. Since you specified DDFM=KR, the test statistic is the one specified in the doc. If you have access to Westfall, Tobias, and Wolfinger (2011, 2nd  Ed), they discuss the LINES option and p-values on pp 280-281. (If you specify an ADJUST= option, the p-values are adjusted.)    I'd like to suggest that the table that the LINES option creates is a poor way to visualize the pairwise significance of the differences. For a discussion, see "Graphs for multiple comparisons of means: The lines plot." You can use the PLOTS= option on the LSMEANS statement to request a better visualization. My favorite visualization is PLOTS=DIFFOGRAM, which creates a faithful representation of the significant differences.       ... View more