Here’s the thing, liquid resin, turning to solid resin, Shrinks.
The larger the area of each layer, the larger the shrinkage forces are.
Moreover- when EVERY layer is equally large, then each successive layer is trying to add its shrinkage to the ones below it.
As the part builds, the first layers warp the most, because they are thin… but as it gets thicker the layers below become more resistant to bending- and so the warping seems to settle down, But not the tensile forces in the resin. Post curing can then exacerbate the warp as the resin body gets softer with heat and the tensile forces in the matrix can more readily bend the material.
As 3D above suggests, the simplest solution is to DESIGN for warpage and be prepared to machine surfaces that need to be exact. Just as cast Wrenches still have machined dimensions where they need accuracy.
Another trick to minimize warpage is to orient the piece to minimize the surface area of each layer as it prints.
Something like this I would print almost on edge, with one corner down and the opposite corner high, so that each cross section was as small as I could get it.