The order in which combo fields effect your attacks seems to be quite bugged. You see, I’m about 90% sure that they are currently working in the reverse of the ordinary order: the most recent ones seem to be taking effect, while the older ones are left to die, cold and alone, forgotten by all.
Now, I’ve only noticed this with the Mortar Kit, as that’s about 90% of my fields that end up stacked — but it’s not just my fields! Sometimes, when I used mortar 5, then orbital strike, my Guardian friend will put down a light field before it fires, and suddenly it goes from delicious double blast heal to… retaliation. If this is intentional, I’ll just say that the old way was better for everything but world bosses, and all of those are fairly easy, save the one everyone is pretty much is aware is all but easy.