User blog comment:D.Dragon123/What we DON'T like about One Piece./@comment-4904935-20130113185846/@comment-53539-20130113203439

Most of the first handful of arcs happened within weeks of each other. :-/

You can see the moon phases up to the Java arc, Its why many worked out the timeline for the first part of OP took place between 6 months-1 year.

Luffy just had a busy year. :-/