Oops, it doesn't look like 'and sar flags on important day' is a national day..

Other days

pick me

Pick Me Day
lumpy rug

Lumpy Rug Day
prosecco

Prosecco Day
self appreciation

Self Appreciation Day
offer

Offer Day
boba

Boba Day
tulip

Tulip Day
stud

Stud Day
kale

Kale Day
nae nae

Nae Nae Day