There's a first for everything I guess. All historical account of Hapkido that I've read documents that above the waist kicks in Hapkido were lifted from TaeKwonDo (some say Taekkyon as well). Everything else is basically variants of those arts kicks.
This Hapkido instructor has a different historical reading.
Beck Martial Arts - Controversial Hapkido Frequently Asked Questions
"The specialty jumping spinning kicks of Hapkido proved very useful for demonstration and breaking purposes and got adopted into Taekwondo"
The source I find give 1961 around the time kicks to waist and above got adopted into most, if not all branches of Hapkido.
It's not entirely out of the question that TaeKwonDo had not yet influenced any martial art at that time but Tang Soo Do surely had, and Tang Soo Do probably had well established practices of spin kicks by 1961.. And Tang Soo Do was the precursor to TaeKwonDo.
This Hapkido instructor has a different historical reading.
Beck Martial Arts - Controversial Hapkido Frequently Asked Questions
"The specialty jumping spinning kicks of Hapkido proved very useful for demonstration and breaking purposes and got adopted into Taekwondo"
The source I find give 1961 around the time kicks to waist and above got adopted into most, if not all branches of Hapkido.
It's not entirely out of the question that TaeKwonDo had not yet influenced any martial art at that time but Tang Soo Do surely had, and Tang Soo Do probably had well established practices of spin kicks by 1961.. And Tang Soo Do was the precursor to TaeKwonDo.