Place it just before the reveal in a travel edit, immediately after the arrival shot, then follow it with footsteps and station ambience as people move through the doorway, keeping the announcement as the clear signal for the scene change.
About this sound
This short Russian voice clip delivers the familiar transit warning that the doors are opening, spoken in a calm, formal announcer's tone over about two and a half seconds. It feels alert and slightly tense, like the brief pause before a crowd moves, and it carries the everyday routine of a busy station platform.