Rolleiflex 2.8f recessed pin besides film rail

Hello. I know the pin is for pushing the pressure plate further when using flat glass . But I wonder when the pin will push the pressure plate. Is it just before film counter reach 1? I tested that and found the pin will loose pressure after film counter reach 1, and will never push out again. That means the pressure plate only lift up away from glass at the very beginning, till the film counter reach 1 . Does someone know how the pin actual work as designed when film winding through? Does it mean that the pressure plate will not lift up again when winding through frame 1 to frame 12?

Don't know. You can pull the side panel off, reassemble winding to make it function, load a roll of film, and watch the pin in action?