问题是，这样就要求要比原来进度规定的完成日期提前六个月完成。

Thee problem is that this is six months prior to the scheduled completion date.

youdao

差异通常包括外部前置任务或外部后续任务的开始日期或完成日期的更改，一般是由于工期、限制、跟踪进度等更改引起的。

Differences usually include a new start or finish dates for the external predecessor or external successor, typically the result of a changed duration, constraint, tracked progress, and so on.

youdao

问题是，这样就要求要比原来进度规定的完成日期提前六个月完成。

The problem is that this is six months prior to the scheduled completion date.

youdao