Or it could just be that the Predictamancers are able to look at future possibilities. The more they see the same thing, the more likely it is to transpire. To use Delphie as an example:
She did ten readings into the future concerning the new heir. In nine of those, a caster was popped instead of a warlord. Of those nine, seven were born female. As the day of the popping came closer, all ten visions were a caster, and nine were female. She knew it was going to be a female caster.
Casting the readings upon the new caster, and playing out the various possibilities. She sees two paths where she immediately turns, and Goodminton is destroyed in the process. One vision involves trading off the new caster, but goodminton still falls 250 turns later. Three images of Goodminton fighting against Haffaton, all eventually losing and the caster joining the other side. One image of the caster destroying the side herself and then joining Haffaton. One image of a peaceful negotiation that the Overlord leads, with Goodminton being subjugated into Haffaton anyway, but at least the units are spared. One image of Delphie doing the negotiations, the caster turns to Haffaton, and Haffaton becomes a bubble side and lives a long happy existence. The last image was a trade negotiation lead by the Overlord that goes sour, everyone dies, and the caster is captured. End result of the prediction: Wanda will serve under Olive.
Knowing the side is screwed no matter which one she chooses, she pushes to try to get the one future where Goodminton survives intact. No such luck, since the fools around here get in the way. Another reading to see the eventual outcome of Goodminton, now that the caster has popped and is on the road sowing Goodminton's destruction. Ten more images. One has a male warlord named Gil finding the note, four have someone named Jillian finding the note, one has a saucy red-headed special agent named Gillian finding the note, one has a princess Jill and her Knave finding the note, one has a pair of warlord finding it, one has the entire Wrecd crew occupying Goodminton (and dying after eating poisoned provisions, but they still found the note), and one has some orc raiding the room and not finding the note (the hat is found 2500 turns later by Ansom when Jetstone rebuilds the city site and he splits off to form his own side). There's a good chance the note will be found. Further readings reveal more details about what happens after the note is found.
Or for the images of Wanda and the Arkentool. One of the initial images may have been Wanda with the Arkenhammer, prying it from Stanley's uncroaked paws after his failed attempt to attack Faq. One may have her wielding the pliers after Haffaton storms Jetstone. Four may have her prying the pliers from Ansom's body, but none of the four have Ansom falling in the same way. Two may show her ridng into battle with a flight of dwagons against Jetstone and claiming the pliers from Ossomer. One may show her attuning to the Arkendish after Haffaton destroys Charlie. Many different points in the time line, and the variable change due to how far out the events are, but in each of them she attunes to an Arkentool. In all but one of those, Faq gets destroyed, and half of them have her as a Haffaton unit. Safe bet, Haffaton is the agent of Faq's destruction, and Wanda attunes to an Arkentool.
Predictions may not be so rigidly set. Delphie may have known that the note would be found (90% chance), but not when. Delphie can know that Wanda will serve as a caster under Olive, but there are many specifics that are too vague to make out until the events in reality get closer to the event that will happen.
Parson is predicted to break war so hard that there will be peace of erf. No immediate details, no specific body counts in that equation, no time frame, and very little specifics. Similar levels of detail are found in the amateur predictamancy thread. The closer the event, the more detailed we make our predictions. Until enough events unfold that we are certain that Wanda is about to split off to her own side, we won't be trying to pin down the exact page in which she splits off. We know that eventually the possibility is there. Once we are within a few pages, we can start plugging in more details into the prediction.