Occasionally NASA will re-analyze the astrometric data to squeeze a little more accuracy out of the orbital determinations for the sake of a mission to a planet to try to hit it with their probe as accurately as possible, but most of this involves careful calibration of very old astrometric data from the pre-digital era, though when a probe arrives they can get even better accuracy using telemetry than can be achieved by optical means. They don't specifically update the "distances" per se.