Arriving Late

In Poul Anderson's The Shield Of Time, it is wrong to think that Wanda Tamberly spent longer than she should have done in 1989alpha AD and therefore she arrived back correspondingly later in 18,2444 BC. Obviously, 18,2444 BC and any version of 1989 AD are not different places existing at the same time but different times. Wanda spent less than a month in the alpha timeline but arrived back in 18,2444 BC a month after she had departed from that year on purpose. Instead of returning, in accordance with Time Patrol rules, to the moment of her departure, she allowed Manse Everard a month to gather intelligence and to get organized to deal with the temporal upheaval without her and her rescued man, Keith Denison, underfoot. Everard thought that Wanda was lost in the divergent and now "deleted" timeline although I still do not understand why he had not even considered the possibility that, like most futureward travellers, she had remained within the Patrol-guarded timeline. Except that - beyond a certain point, the options become too complicated for clear story-telling.