Linkedin interview expedite possible ?

1) How long does the Linkedin interview process take in general ? Can it be completed in an expedited manner ? 2) Do phone screening interviews also need Hiring Committee approval ? 3) How often does the hiring committee convene ? 4) Is the offer created after Hiring Committee approval, or only after team match is completed ? Situation: Have an offer, but interested in Linkedin and the process has not even formally started 🙁