For a reason at the supplier, the shipment will be split into a couple of deliveries.
具体的な出荷日を続けたい場合には、回答文の最後をコロン（：）に変えて、日付を列挙すれば良いですね。例えば、
”For a reason at the supplier, the shipment will be split into a couple of deliveries: the 1st on Nov 15, and the 2nd on Nov 30.”
For the convenience of the supplier, this shipment will be split into separate of deliveries.
For the convenience of the supplier, this shipment will be split across multiple deliveries
この文章が以下のように翻訳されています。
サプライヤの都合で、この部品は分割で出荷します ー For the convenience of the supplier, this shipment will be split into separate of deliveries.
サプライヤの都合で、 ー For the convenience of the supplier / to make things easier for the supplier / due to supplier constraints
この部品は ー this shipment / this delivery / this order
分割で出荷します ー split into separate deliveries / split across multiple deliveries
参考になれば嬉しいです。
日本 
オーストラリア 
