In addition: The group-speed may not be lowered more than 30% by new ships. If new fleets are slower, the option for a group-attack is not available!

• 另外,群体总速度不能比原来的舰队速度慢超过30%25,以到达时间计算。如果新的群体速度要慢过这一限制,那么这只舰队不能参加联合攻击。