According to a press release dated 16 November 2021, the Banco Central de Nicaragua announced the introduction of revised 50- and 200-córdoba notes with tactile elements at lower right front that facilitate identification by the sight impaired. Additionally, security has been improved with the addition of iridescent bands on the backs of the notes. These images change color depending on the angle of inclination and lighting. Preceding issues will continue to circulate in parallel.
Like B510a, but new date (26 DE ENERO DE 2022), tactile embossing at lower right front, and Iridescent band added on back.
Courtesy of Alex Zlotin, Flavio Jose Garcia Polanco, Don Ludwig, and Stane Straus (polymernotes.org).