As from October 11, 1939, Pelikan fountain pens were fitted with chromium/nickel (CN) - steel nib, as the use of palladium nibs for the domestic market was forbidden by the government. Please refer to Pelikan 100 (ca.1940) for further information on CN nib. Some export market pens had gold nibs.
In early 1940's, Günter Wagner introduced new material, acrylic plastic to the barrels (Green book). With the introduction of acrylic plastic, model 100N went into the "3rd generation". According to @stoen's observation, at first, Günter Wagner manufactured injection molded acrylic plastic barrel with cellulose acetate stepped section (Fig.1 right). Around the same time, the company manufactured injection molded acrylic plastic barrel with cellulose acetate stepless section (Fig.2). The reinforcing ring was no more installed. These model are likely to be transitional models to Pelikan 100N (ca.1942). For further information on these models, please refer to Pelikan 100N (ca.1942).
Fig.1. The grip section of model 100N. Left; ebonite (ca.1937), right; cellulose acetate (ca.1940). By courtesy of @stoen.
Fig.2. Model 100N with cellulose acetate stepless section and acrylic plastic barrel (ca.1940). By courtesy of @stoen.