ok.. this flag of nepal was used after jung bahadur became Shree teen maharaj. Originally the flag of nepal was the flag of the king (shree panch), which is the upper triangle with the crecent and sun. The flag of the shree teen was the lower triangle with the sun. Once the wedding was confirmed of the daughter of King Surendra and son of Jung Bahadur, they also decided that the flag be joined to make one flag that represents the family and the country. Thus the new flag with double triangle was born. so, if the national anthem is changed citing to remove the King's rule, then the flag should also be changed. However, my stance is with the monarchy so, do not change the flag and the national anthem.