@User this can be solved by editing file (example for tt corner):

sky130_fd_pr__pfet_01v8_hvt__tt.corner.spice

and letting it include

sky130_fd_pr__pfet_01v8_hvt__tt.pm3.spice

instead of

sky130_fd_pr__pfet_01v8_hvt.pm3.spice

the default included file has 'point-size' binning , as it defines points instead of regions. the

_tt.pm3.spice

file defines reasonable continuous regions. This change is already done for nfet_01v8_lvt if this patch is applied (fixes the temp->temper and tempo coefficients issues in resistors, contribution from @User). Curious enough is the fact that for other transistors (example: pfet_01v8_lvt) this

_tt.pm3.spice

is already the default included file. I can update the patch file to make the change for these p_hvt transistors. I usually work with this patched version of the spice models as i was too much bored of these error messages. Needless to say, it must be verified if the accuracy is acceptable when using these binned models outside their 'point-sized' existence regions.