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

Other days

cuddle up

Cuddle Up Day
artists

Artists Day
coffee

Coffee Day
slime

Slime Day
stud

Stud Day
azonto is acceptable

Azonto Is Acceptable Day
nae nae

Nae Nae Day
bounce

Bounce Day
camera

Camera Day
ride the wind

Ride The Wind Day