手机排版请见谅。
今天收到一封美国同事A写的信如下：
The current status of PO 7721 is that it has dropped to delivery and will arrive on July 14th. PO 7810 is not scheduled to arrive to you until August 18th.
但信件内容有包含美国同事A询问美国同事B出货进度的纪录，
同事B回复A的内容如下：
We agreed that the 1759 pieces would be available against PO 7721 on 06/26/2014. The delivery has dropped accordingly. The balance will be available on 07/14/2014.
两段信件对进度的资讯及结论似乎彼此冲突，
其中"the delivery has dropped"更是让我们摸不著头绪。
请问该如何解释这里的drop呢？
谢谢~