One of the bases near "Nuclear Production Complex" has shut my attack down... twice. Last time I was arond wave 70 when it ended. I could just barely scrach their core bases with each attack. Several hours...

I had to give it a break after that. I was routing conveyors in my dreams but with a perpetual sense of doom.

Good game though. I really like how it addresses any gripes I have when playing factorio. The whole time I felt it was a little easy, but not anymore!

I'm in the same boat. I've made some headway but they weren't kidding, it's hard! I'm still struggling on new maps managing my time between building defenses and ramping up industry. I definitely prefer the part after finishing waves where I can relax and perfect my build.