Oops, it doesn't look like 'mass choir evening session day' is a national day..

Other days

camera

Camera Day
african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
stress awareness

Stress Awareness Day
hiv awareness

Hiv Awareness Day
prosecco

Prosecco Day
bonang

Bonang Day
self appreciation

Self Appreciation Day
appreciate yaself a lil extra

Appreciate Yaself A Lil Extra Day
bow tie

Bow Tie Day
slime

Slime Day