Here are the results from running PROBE_ACCURACY in all four corners:
Front right at probe at 317.500,37.500
probe accuracy results: maximum -0.275625, minimum -0.288750, range 0.013125, average -0.285750, median -0.286875, standard deviation 0.003769
probe accuracy results: maximum -0.271875, minimum -0.286875, range 0.015000, average -0.282562, median -0.284062, standard deviation 0.004112
probe accuracy results: maximum -0.275625, minimum -0.286875, range 0.011250, average -0.284437, median -0.285937, standard deviation 0.003462
probe accuracy results: maximum -0.266250, minimum -0.281250, range 0.015000, average -0.277500, median -0.279375, standard deviation 0.004743
probe accuracy results: maximum -0.264375, minimum -0.283125, range 0.018750, average -0.277875, median -0.279375, standard deviation 0.005675
Front Left
PROBE_ACCURACY at X:57.500 Y:37.500 Z:1.715 (samples=10 retract=2.000 speed=5.0 lift_speed=50.0)
probe accuracy results: maximum 0.037500, minimum 0.011250, range 0.026250, average 0.019875, median 0.017813, standard deviation 0.007556
probe accuracy results: maximum 0.026250, minimum 0.007500, range 0.018750, average 0.012375, median 0.011250, standard deviation 0.005447
probe accuracy results: maximum 0.020625, minimum 0.003750, range 0.016875, average 0.008813, median 0.007500, standard deviation 0.005104
probe accuracy results: maximum 0.018750, minimum -0.001875, range 0.020625, average 0.006000, median 0.003750, standard deviation 0.005675
probe accuracy results: maximum 0.202500, minimum 0.178125, range 0.024375, average 0.184875, median 0.181875, standard deviation 0.007075
Back Left
probe accuracy results: maximum 1.066875, minimum 1.050000, range 0.016875, average 1.053750, median 1.052813, standard deviation 0.004961
probe accuracy results: maximum 1.066875, minimum 1.050000, range 0.016875, average 1.053375, median 1.050938, standard deviation 0.005155
probe accuracy results: maximum 1.068750, minimum 1.048125, range 0.020625, average 1.053000, median 1.050938, standard deviation 0.006173
probe accuracy results: maximum 1.080000, minimum 1.051875, range 0.028125, average 1.062563, median 1.061250, standard deviation 0.007642
Back Right
probe accuracy results: maximum 0.127500, minimum 0.114375, range 0.013125, average 0.119625, median 0.119063, standard deviation 0.003437
probe accuracy results: maximum 0.163125, minimum 0.148125, range 0.015000, average 0.150938, median 0.150000, standard deviation 0.004296
probe accuracy results: maximum 0.193125, minimum 0.176250, range 0.016875, average 0.188625, median 0.191250, standard deviation 0.005447
probe accuracy results: maximum 0.226875, minimum 0.202500, range 0.024375, average 0.208313, median 0.206250, standard deviation 0.006887
probe accuracy results: maximum 0.243750, minimum 0.217500, range 0.026250, average 0.223500, median 0.219375, standard deviation 0.007676