I would requalify the problem.
Since no axis is on overtravel condition ( we don't know for sure without the screen with system coordinates and axis stroke limit parameter values ) the problem is that "axis overtravel cancel" is on. We don't know how and where. For this age machine it should be a tumbler.
or
The OSP goes to that wrong status by mistake, is frozen but powers on the hydraulic system ...
One more question. Check if the contactor supplying power to spindle drive, the contactor supplying power to ZA drive and the contactor supplying power to XA drive turns on after OSP boot.