The distinction between "plural" and "dual" has always escaped me. Maybe someone will post here, and clarify the titles to me. I have been interested in this for some time. Some Grand Lodges permit you to join one (1) lodge only. (Ex: West Virginia). In WV, when you apply for affiliation (and you are already a MM), your application must be accompanied by a demit from your previous lodge(s), or else you are committing a Masonic offense.
Some Grand Lodges permit you to join one lodge in their jurisdiction, and as many as you like, as long as they are out of state.
California permits you to join as many lodges as your "checkbook can handle".
Some lodges in rural Texas, are only able to survive, because the GL of TX permits plural memberships, and men can "commute" between lodges, and keep some of these small lodges open.