Has anyone done testing on intensity and rounding?

I ask this because with winds of magic reduction costs being changed or bugged with the transition to wh3 I am curious how the damage works.

Does a 6 ap spell round to 6.5, stay at 6.6 or round up to 7 with 10% intensity? 4 is another common number, does it round down to 4 or stay at 4.4?