What's the "Free" icon I see when I Upgrade my buildings? | Pirates of the Caribbean: Tides of War

Pirates of the Caribbean: Tides of War Game Game play

What's the "Free" icon I see when I Upgrade my buildings?

If you have less than 5 minutes, the icon will show up.

When you tap the icon, upgrade will be completed immediately.

※ Free construction time depends on your VIP level.

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