Kew Gardens mezzanine bus stop

I recently discovered an article that hypothesized that buses once stopped at the mezzanine level of Kew-Gardens Union Turnpike where Union Turnpike passes under Queens Blvd (today, where the glass blocks line the station by the highway). Does anyone know if/when buses operated like this, or just have any information about this?

A Canarsie-style bus stand within the station would be so much more convenient for bus passengers than today's multi-block layout.