were any changes made to the flag?
Yes, the second version of the national flag was developed in 1956
Flag of Bhutan
The second version of the national flag was developed in 1956 for the visit of the third Druk Gyalpo Jigme Dorji Wangchuk to eastern Bhutan.
what is the name of national flag of bhutan The flag features a dragon from Bhutanese mythology
wiki:19093555
Flag of Bhutan [SEP] Changes in 1956
The second version of the national flag was developed in 1956 for the visit of the third Druk Gyalpo Jigme Dorji Wangchuk to eastern Bhutan. During the trip the Druk Gyalpo's Secretariat began to use flags of a new design based upon a photograph of the first national flag of 1949, with the colour of the dragon changed from green to white. The retinue of the Druk Gyalpo included a convoy consisting of over one hundred ponies; a small version of the flag was placed on the saddle of every tenth pony, and a large flag approximately in size was flown in the camp every evening, hoisted to the sound of a bugle.