As it was uploaded on the fan's social media account where the video cannot be edited, it is for sure that the song was produced before November 2015.
After the discovery, the video started to go viral among fans.
Fans have been commenting on how surprised they were to find out that 'Forever Young' was ready to be out even before the group's debut in August 2016.Meanwhile, BLACKPINK returned after a year with a double title track 'Forever Young' and 'DDU-DU DDU-DU' on June 15.