Not a lot of details out yet, but here is the article
Special offer for Alaska Visa Signature cardholders – coming soon!
Later this year, when using an Alaska Airlines Visa Signature® card to pay rent through Bilt, cardholders will be eligible to earn triple Alaska miles – 3 miles for every dollar spent on rent up to $50,000 annually. This innovative offering will reward Alaska’s loyal cardholders on their largest monthly expenditure. Terms, conditions, and fees apply.*
h/t travduke