The process took 3 weeks from first contact email, to interview result phone call. As I have signed an NDA, I can not speak too much about the process, just that it is a more real life scenario, rather than a test of generic algorithm questions such as sorting etc... Thus, in terms of preparation, you cannot cram for this, you need to have a good understanding of engineering as whole, and how to apply it.

I had a first phone screen, which was an hour long, had 15 minutes of Hr questions based on Leadership Principles, then 45 minutes of real-time coding problems, You need to know a bit much about DSA to be able to pass the coding challenges, you must think out loud.