As described in 76326 "kappa_TST is the time-dependent correction factor that tracks the TST stage actuation strength relative to the last time the calibration was updated", but the calibration hasn't been updated more regularly, so if it was still changing, we should see it. Francisco has made a script to automatically adjust the ETMX L2L drivealign to compensate for Kappa_TST but this only started this week: 78425.
In October Ryan's anaylsis showed the Kappa TST drift agreed up with increasing charge on ETMX from in-lock charge measurements: 73613, recent in-lock charge measurements in 75456 show the charge hasn't changed much. To do: check on in-lock charge measuremtns and add a longer time scale plot.