If I set the LDA score below the default value of 2.0, is it still statistically reliable?

I understood the LEfSe analysis (KW, Wilcoxon), but I am still not sure if I can adjust the default score.

Our data shows very few different species for a score>2.0 . (Independent variable is two, before and after.)
So I want to adjust the default score. Is there a problem if I do it?