Oops, it doesn't look like 'TeamA Big day' is a national day..

Other days

hoodie

Hoodie Day
donate your hair

Donate Your Hair Day
lisp

Lisp Day
polyamory

Polyamory Day
lumpy rug

Lumpy Rug Day
unicorn

Unicorn Day
china

China Day
prosecco

Prosecco Day
latina equal pay

Latina Equal Pay Day
comfy

Comfy Day