Reclaiming Blingdenstone Question about Chapter 1 Mission

I started reading through Blingdenstone to prepare in using it for a new group in the next few weeks.

In reading through Chapter 1, the Pech leader tells you that they will help if you are willing to take care of the orcs and kobolds. Do you read this as the Pechs saying they'll help if the characters promise to take care of the orcs and kobolds at some point in the future, or only after the characters have taken care of them and returned to the Pechs?

I know I can run it either way if I choose, but what do you get the intended idea of the text to be?
For me it mostly depends on PCs' attitude and common sense. Were they nice and polite? Did they treat pechs with respect? In my module I stated for myself that peches will only decide to help if they see at least one real deed from the party (destruction of orcs/kobolds or negotiation with gnomes)
Thanks hirou, I like that idea.