I was referring to the waveyness in the center, though the warping on the esges is partly caused by both the oils and the cooling shrinkage, I believe.
The uniform buckling of the layer in the middle of the sheet is what I'm leaning on, but I don't believe that your fan speed is too high, or there would be more seperation between layers as the filament would cool too much before adhering to the layer below.
I believe there are test STLs that assist in Dialing in your settings for printing plates in particular, but I'm avoiding printing surfaces that large until I get an enclosure built.
Only because the C-suites' don't have a creative bone in their collective bodies. They only know how to follow 'numbers go up!'