Having defected to the Kohlin warcamp during the chaos of the Aftermath of The Battle of the Tower, the survivors of the failed Temple Expedition with Bridge 9, Lan and Eutimio, were quickly promoted to training former bridgemen with bow and spear.
Meanwhile, Ayya was studying and networking with ardents and scholars of many of the warcamps. He ran into Tazo, who was excited to see him and hear about their friends in the Kohlin warcamp. Tazo also had news of a caravan, still a few weeks out, that he, for some reason, wants help getting on the protection detail for.

A week or more after The Battle of the Tower, Lan and Eutimio were approached and offered a scouting mission... and encouraged to bring any friends they might have who were interested in hazard pay.

The Messenger:
"I have a message from Capt. Kaladin, sir. He wanted me to offer the two of you a "VACATION". It seems that Sadeas has been sending spies into the warcamp to look for defectors. So... um... "Officially":
Scouts have detected an unexpected sight: signs of a large signal fire off towards the north end of the Shattered Plains. While investigating, the scouting party was chased away by a group of enemy scouts. We assume they’re trying to track down the same mysterious signal. Whatever is out there, we need to beat the enemy to it and, considering you lot have proven capable of surviving out there and dealing with enemy scouting parties, Kal thought we should offer you gents the opportunity to do it again.

Find whoever started that signal fire, and why. If there is an advantage to be gained out there on the plains, it is your mission to make sure we gain that advantage... or that the enemy does not.

Stock up on rope, vaulting poles, grapple hooks, whatever you need... within reason, mind.
... Oh, and bring a "friend" or two, won't you? If you got any? Anyone you can think of who might want to get away from camp for a few days? You get the picture. Full hazard pay for up to six squad members. Trouble will be after you out there almost as much as it is in here."