Yes, miles earned through the China Airlines Dynasty Flyer program are subject to a strict expiration policy. In 2026, miles are valid for 36 months (3 years) from the date of the flight or the date they were credited to your account from a partner activity. Unlike some Western loyalty programs where any account activity (like a small purchase or a credit card transfer) can reset the clock for your entire balance, China Airlines operates on a "hard" expiration system. This means that individual blocks of miles will expire exactly 36 months after they were earned, regardless of how many new miles you add to your total. It is important for members to track their "Mileage Validity" section in the Dynasty Flyer app or website, as once these miles expire, they cannot be reinstated or extended. During 2025 and 2026, certain temporary adjustments were made to partnership accruals (such as with China Southern), but the core 36-month validity remains the standard for the program's flagship rewards.