This close to finish... Yeah, it doesn't sound like there is much you're going to be able to do that will affect the final result at this point. Ride it out, I guess.
That's P defc. caused by pH lockout,... you'll have to correct the in-pot pH, likely by flushing,... there's lots of P in there, just not in absorbable forms now,... that EC seems high for Autopots too,... how close to finish are you? A flush is done with low ppm water, 2-3x pot volume,... take the input water's pH first, then flush,... check the pH and EC of run-off after a pots worth of flush to see how well it's clearing, and occasionally after that to monitor progress,...
