The 12-hour shield rule is aimed at stopping unfair players who use special programs to stay online for 24 hours a day and make it impossible to attack their bases.
The "shield" only protects your island from attacks by other players and doesn't affect Strike Group Battles.
The length of time you are safe from attack is now limited to 12 hours a day. If you spend more than 12 hours in the game, you can still be attacked, even if you are online.
If the effect of the "shield" has finished and your island is attacked, you will get the following notification:
Resources will be taken at the same time you receive the notification.
The protection lasts for 12 hours a day and begins from the moment you load the game. When you leave the game, the timer stops. The "shield" is refreshed at precisely midnight Moscow time.