Whole day assessment centre: Numerical test, 10 minute presentation with very few competency questions, group exercise and technical interview. Numerical test is exactly the same style as online testing. Hard to go wrong with the 10 minute presentation, focus on your experiences and what you've learnt that makes you a valuable engineer. Technical interview - the hardest part. You can only prepare so much because the interviewer finds out the limit of your knowledge quickly and asks things you don't know to see how you react. Being familiar with engineering basics (e.g. materials processing) definitely helps.

Two interviews, one detailing previous work experiences (general interview question), and a second which was a more challenging technical interview. There was also a numerical test, to verify online scores, pretty easy. Group exercise also which was fine, just typical team building exercise. Whole day was well structured, and I heard back within 48 hours which was great.