急～美国专利PTA计算：overlapping days between A and B delays

A delay: 398
B delay: 506

为什么 overlapping days betwwen A and B delays是94天呢？非常感谢！

A delay and B delay are calculated differently. The overlap is the actual calendar delay, not necessarily the difference between A and B. Technically, it could be from 0 to 506.