Oops, it doesn't look like 'flags to passengers on day' is a national day..

Other days

Kale Day

Tell A Fairytale Day

Prosecco Day

Donate Your Hair Day

African Immigrant And Refugee Hiv And Hep Awareness Day

Tell Ur Crush You Like Them Day

Pumpkin Day

Stud Day

Aloxolt Day

Pampering Day