In Chapter 55, Herbert proposes that Pip should come with him to Cairo. Herbert is going to be going to Cairo to run a branch office. He suggests that Pip should come with him and start out as a clerk. He tells Pip that there is a chance that Pip could work his way up and become a partner.
Pip is not able to give Herbert an answer right at this moment because he is preoccupied with Magwitch's troubles. Later in the book, Pip decides to take Herbert up on his offer and does go with him to Cairo.