According to the Archives of Audemars Piguet, watch number 45'966 was sold in 1944. As the movement and case numbers of the present watch are different, it can be assumed that a change has been carried out during a servicing of the watch.
This simplified World Time system was designed as a memory aid, facilitating the determination of the time differences between various cities of the world. These dials were available in different versions as to the "main" or "home" location which on the present watch is New York, indicating that at noon New York time, it would be one o'clock in the afternoon in Buenos Aires, midnight in Singapore and so on.
For different versions of such "World Time Dial" wristwatches see Audemars Piguet by Gisbert L. Brunner, Christian Pfeiffer-Belli, Martin K. Wehrli, second edition, pp. 219 - 221.