Ok, Put down 3 coats of Bona Mega Satin on a stained, water-popped oak floor. Owner had a BIG dog that scratched it up right off the bat, so we went back to put on 2 coats of traffic. Here's the deal : the resulting finish has TWO different sheens. That regular Traffic Satin look, and then it looked like Semi/Gloss in a 150 sq ft section of the floor. The total floor space was 900 sq ft.The same Sand/Stain/Finish/Abrade process was used like we do on all our jobs. Does anybody know why this would happen, only a section of the floor coming off with a different sheen from the rest ???????????????????? Also , the Activator/Finish mix ( A/B ) was exact like we always do

Well, did you work out of two containers? Was one mixed more thoroughly than the other?
Even if from the same bucket, a sheen difference can occur if not completely mixed before separating into multiple containers.

Dennis's suggestion is the most logical. Aside from mixing, the only troubles I have had to deal with that cause sheen problems are air flow over the drying finish.Make sure that there is zero air flow on your final coats.

mill thickness will give you trouble as well. Traffic is reccomended to put on heavy. if you get it thin it will streak and or show diffrent sheens. Did a diffrent guy coat those sections?

I worked out of fresh containers for all coats, i never mess around with Traffic ! That "Airflow" theory sounds spot on because it was their back patio/Breakfast area with a lot of vented windows and a screen door. I was baffled, never came accross this before. Thanks for the responses Guys.