Switch to other Big 3.

Hey folks I'm from Civil engineering background currently working as Scon (June 24). My experience is 13+. I'm expecting promotion to M with a decent hike, however, also want to keep a plan B. How to look for opportunities in other B3? I don't have much idea about it. I have core expertise of civil engineering and BIM, but don't have any links or way to look for Civil related jobs in B4. I heard there are roles in advisory, audit, capital projects as well. Kindly help here.