it looks like I will need to invest in 4-6 fast 128gb cards.
I'd seriously consider waiting until we know what the new camera actually has.
128 multiplied 8 to make Gigabits from those gigabytes, diveded by 0.4 Gigabits (400 Megabits) = 2560 seconds or 42 Minutes, 40 Seconds - I guess, if it's really only 36 Minutes then there's either some overhead or it's a bit more than 400 Mbit/s.
You are correct. I was referencing VaricamLT which is a bit more so its a little conservative if the new camera is 400Mbps