I have never purchased a premium but activated an 1-day premium some months ago for free in an event, and after that every day when I play the “Your Premium Account has expired. Would you like to subscribe now?” box shows up. How can I avoid it showing up again?
Buy a premium account? lol.
That requires some config editing.
Navigate to Documents > My Games > WarThunder > Saves > (some numbers) > production.
Find global.blk, open it in notepad.
Search for PremiumReminder, there should be a numerical value there.
Add a couple of 9s to that value and save.