A sortation conveyor has an endless apron supported for longitudinal movement on an elongate frame that includes a pair of lateral side frames. An induction conveyor deposits articles on an offset lateral portion of a top conveying run of the apron. A pin guide assembly is coupled between the pair of lateral side frames and is upwardly presented to selectively receive the pin of pushers that laterally move across the apron. An upstream pre-sort section thereof positions articles from the offset lateral portion to an opposite lateral portion of the top conveying run. A downstream divert section of the pin guide assembly selectively diverts the articles to a divert target on the corresponding lateral side to the selected one of offset lateral position and the opposite lateral position.