I have found a problem with %pl x_max setting. If I try to set x_max to any value above the actual data range, it uses my value quite happily But if I set x_max to a value below the actual data maximum, it ignores my supplied value and uses its own. This doesn't seem to happen with y_max where it always accepts my y_max whether above or below the actual data maximum.
3 sample plots. (1) I don't set any x y limits (2) y_min=40 y_max=110 (3) y_min=40 y_max=110 and x_min=7000 x_max=7500 (x_max effect is the same with or without the y_min y_max settings)
