You are correct.

Molasses or treacle is a thick syrup by-product from the processing of the sugarcane or sugar beet into sugar. The sugar cane plant is harvested and stripped of its leaves. Its juice is extracted from the canes, usually by crushing or mashing. The juice is boiled to concentrate and promote the crystallization of the sugar.

The results of this first boiling and removal of sugar crystal is first molasses, which has the highest sugar content because comparatively little sugar has been extracted from the juice.

Second molasses is created from a second boiling and sugar extraction, and has a slight bitter tinge to its taste.

Gotta love Wikipedia!