"I'd figured it at perhaps two hours before sunrise," Dowland said.
"What would hold them up?"
"They can't climb the mesa at any point near the ranch by night.
A descent might be possible, but even that would be difficult and
dangerous. And they'll be carrying repair equipment to take care of
whatever's gone wrong. So they'll have to come up the northern end,
where it isn't so steep."
"And then," Dowland said, "they still have to come down across the
mesa on foot. Makes sense. And, of course, that messenger actually may
not get here before tomorrow. If he comes then, at what time would he
arrive?"