If you did not know, EVE-o solved timezone issues… 15 years ago.
They simply run two battles on each contested checkpoint, one when attacker decide, and the following one when the defender wants (but no later than, say, 48 hours since initial attack, that brought the checkpoint into reinforced state).
And this is about instant capture of the checkpoints. SoH back in the day had a deterring mechanics that prevented occupants from fully controlling the city right after capturing, so a defender could fight back and recover control within a reasonable time frame (the longer, the more population the city had).
They simply run two battles on each contested checkpoint, one when attacker decide, and the following one when the defender wants (but no later than, say, 48 hours since initial attack, that brought the checkpoint into reinforced state).
And this is about instant capture of the checkpoints. SoH back in the day had a deterring mechanics that prevented occupants from fully controlling the city right after capturing, so a defender could fight back and recover control within a reasonable time frame (the longer, the more population the city had).