AviationTire Air Law And Atc Procedures Annex 14 - Aerodromes Visual aids for Denoting Areas of Restrictive Use Q 4 / 5

The pre-threshold area of a runway fit for use by aircraft as a stopway, but not for normal movement of aircraft is marked with:

white arrows directing approaching aircraft to the displaced threshold
yellow chevrons pointing towards the threshold
a yellow X
a white X