The notations from the database for LX, LA, LP are typically:
LP = Lift-Trace-Previous
LA = Lift-active-close
LX = Lift-trace-finished
LC = Lift-trace-close
X = older lifts????
It appears that that the "LX" designation in the file represents the newer excavations whereas the database includes the notation that the "X" (without the "LX") represents the approximate outline of older stopes. These "X" files are much more common in the upper parts of the underground.