The secret here is that if you pass R1, you can do the job on a good day. R2 is now about consistency of performance, fit and understanding whether your weak spots from R1 were just a bad day or a real issue.
In R2, try not to repeat the same mistakes if you had any in R1. Focus on behavioral questions. Prepare for some open-ended case questions (once I got "Mayor of London wants to monetize citizen data, how should he?).