The period between December 18th and January 1st 2017 gave players 14 days of gifts. Players regard it as the most perfect time in life/the game of Fortnite.
Sometimes, it is used as a compliment to say someone is perfect. It is more often used by males, but not exclusively.
As his girlfriend was preparing for their date, she asked,
"How do I look?"
He took one look at her, and in a nostalgic, bittersweet tone; spoke the words:
"14 Days of Fortnite"
This meant absolutely nothing to her at the time, but one urban dictionary search later revealed what he meant.