Once you pass the phone screening and submit the code you will be invited to a pair programming code challenge. I would recommend to be relaxed and and communicative. Try to articulate well and reason about the problem given. The interviewers are very senior and skillful they will answer your questions. The code itself its something you can do or should be able to do in an hour. So its a realistic expectation.

Initial phone screening interview. Then a fizzbuzz coding test to demonstrate TDD. Unfortunately according to agent the position in which I was to be placed was no longer required, so the process stopped there for me, and I don't know how well I did.