Problem When Setting Alerts

I am having a problem setting an alert when the flight is leaving from airport across the Dateline.
Example China Eastern flight 523. I am in Eastern timezone, the flight departs Shanghai (ZSPD/PVG) at 09:05 CST which is 21:05 Eastern.
However the departure is on sept 22 (departure airport) which is Sept 21 Eastern. If I set the Alert for Sept 22, I miss the flight, If I set it for Sept 21 I get the flight.

Thank you for the report. We will look into it. What device were you setting the alert up on, web or app?