Do you see something abnormal in following image?
Yes …….what’s this ……?
And same thing you will see on some other ERP solutions / software once you select September 1752.
The calendar snippet shows that there are no days between October 4 and October 15. This discontinuity is called the “cutover”.
What is Cutover
“This is a hybrid Julian/Gregorian calendar with a cutover on October 4/15 1582.” Any dates before a cutover are Julian, any dates during a cutover are nonexistent, and any dates after a cutover are Gregorian.