Changing your WOO outside the NA window is allowed.

src/engine/net/client/handlers/MineWindowChangeHandler.java

@@ -96,7 +96,11 @@ public class MineWindowChangeHandler extends AbstractClientMsgHandler {
 			return true;
 	}
 
-		if (newMineTime <= LocalDateTime.now().getHour()) {
+		// Cannot set a time to a window that has not closed if mines are currently open.
+
+		if (LocalDateTime.now().getHour() >= MBServerStatics.MINE_EARLY_WINDOW &&
+				newMineTime <= LocalDateTime.now().getHour() &&
+				LocalDateTime.now().getHour() != MBServerStatics.MINE_LATE_WINDOW) {
 			ErrorPopupMsg.sendErrorMsg(playerCharacter, "You must first wait for that mine window to close.");
 			return true;
 		}