Oops, it doesn't look like 'police on the fifth day' is a national day..

Other days

lumpy rug

Lumpy Rug Day
promposal

Promposal Day
bow tie

Bow Tie Day
stud

Stud Day
buddy

Buddy Day
tulip

Tulip Day
bounce

Bounce Day
prosecco

Prosecco Day
kale

Kale Day
singles

Singles Day