due China's three major airlines will raise jet fuel charges on international flights from next week.The surcharge increase,due to start around October 1,will vary from route to route depending on the destination and airline.

due China's three major airlines will raise jet fuel charges on international flights from next week.The surcharge increase,due to start around October 1,will vary from route to route depending on the destination and airline.
due
China's three major airlines will raise jet fuel charges on international flights from next week.
The surcharge increase,due to start around October 1,will vary from route to route depending on the destination and airline.

due China's three major airlines will raise jet fuel charges on international flights from next week.The surcharge increase,due to start around October 1,will vary from route to route depending on the destination and airline.
The surcharge increase,（which is）due to start around October 1,will vary from route to route depending on the destination and airline.
不是due to,而是due to do sth...
预期做某事或到时间做某事...

计划

额外费增量到期在近10月1，将会开始变化从路线到路线根据目的地和航空公司。
The surcharge increase, due to start around October 1
到期-due to

due date是指付账日期，due在这里是指到期的意思，这里是说
10月1日左右开始的超载提价将根据目的地、航线，每条路线都有所不同。

计划
due to start+时间 通常可放一起使用，表示计划将从....开始。

because

be about to
计划于