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

Other days

buddy

Buddy Day

tell a fairytale

Tell A Fairytale Day

prosecco

Prosecco Day

Emoji Day

cuddle up

Cuddle Up Day

brow

Brow Day

slime

Slime Day

boyfriend

Boyfriend Day

polyamory

Polyamory Day

tell ur crush you like them

Tell Ur Crush You Like Them Day