The decay data told a story. Kael and Mara spent two hours in the Veil Office archive that afternoon going through eleven months of frequency monitoring data point by point, Cross sitting across the table from them and watching them work with the expression of a man observing a process he understood well enough to know he could not replicate it.
The story the data told was precise and not comfortable. The port district entity had entered Veil Office containment eleven months ago. In the first three months, the city-wide decay rate had been consistent with the long-term average, gradual deterioration, the kind of slow boundary erosion that had been present for as long as the Veil Office had instruments to measure it.
In month four, the decay rate had increased by two percent above the running average. In month six, it had increased by four percent. In month nine, by eight percent.
The night of the Southgate breach, the night the port district entity had returned through the basement crack, the city-wide decay rate had jumped fourteen percent in a single measurement period.
Kael looked at the graph Mara had sketched from the data points. The curve was not linear. It was exponential.
"The entity was feeding information back to the Rift in real time," Mara said. "Not all at once at the end. As it read the archive, it communicated what it read back through the basement crack progressively." She traced the curve with her pencil. "Each increment of information allowed the coordinating intelligence to refine its approach to the decay acceleration.
The jump at the end was because the entity had completed the archive and confirmed all the information in a final transmission before returning."
"They know everything Cross knows," Kael said.
"They know everything Cross knew eleven months ago," she said. "And they know the development trajectory of his monitoring capability based on the historical data in the archive."
Cross was looking at the graph. He was not looking at it with the expression of someone seeing surprising information. He was looking at it with the expression of someone seeing confirmed information they had hoped would not be confirmed.
"You already ran this analysis," Kael said.
"My team ran a version of it this morning," Cross said. "Their version did not include the progressive communication hypothesis.
The single final transmission theory was the working assumption." He looked at Mara. "Your version is more consistent with the granular data."
"The progressive theory also better explains the three remaining directed pressure sites," Mara said. "If the coordinating intelligence had the full archive from the beginning it would have acted sooner. The refinement of approach over eleven months is consistent with information arriving in increments."
"Which means the three remaining sites were not in the original plan," Kael said. "The four-site approach was refined from a smaller original plan as the archive data provided better information about boundary vulnerabilities."
Cross looked at him.
"Meaning the original plan had fewer sites and less ambition," Cross said.
"Meaning the original plan grew as the intelligence grew," Kael said. "We are not dealing with a fixed program. We are dealing with something that learns and adapts."
The room was quiet. Mara wrote on the whiteboard Cross had provided, which she had been treating as an extension of her own system since she arrived.
DECAY RATE: EXPONENTIAL. NOT LINEAR.
CURRENT ACCELERATION: 14 PERCENT ABOVE BASELINE.
PROJECTED TIMELINE TO UNCONTROLLED BOUNDARY FAILURE: 12 TO 14 DAYS AT CURRENT RATE.
RATE WILL INCREASE. ADJUST TIMELINE DOWN.
She stepped back and looked at it.
"Twelve to fourteen days," Cross said.
"At current rate," Mara said. "The rate will increase. I would plan for ten."
Cross picked up his phone. Kael looked at the whiteboard. He thought about ten days and what needed to happen in them. He thought about the other four members of the six he had not yet found.
He thought about the owner of the Ledger, four hundred years old, waiting at the boundary of the Open, watching the decay accelerate.
He thought: the owner released the scaffolding. The owner started the acceleration.
He thought: because the owner is ready.
He thought: are we ready?
He looked at his mark.
The convergence point stared back at him, dark and patient and building.
Not yet. But close.