Beat me to it Randy - agreed, when you turn off shadows, boom, fps problems on the deck over enemy bases disappears. With 980/ti/sli cards it's the same experience for me as those above, although I only drop into the high 40s at worst, usually low 50s is the lowest I see, but here and there 45 to 49 on the deck with the same criteria as those above. I tried every combination of settings as well, and found that shadows off makes the fps jump back up to 144 or 165 depending on which monitor I'm using.
Game sure looks good, can't wait for it to be live, it's going to be a pile of fun, just in time for new hardware upgrades too.