I applied through my school's career services website and was invited to interview on campus. It was a 1-on-1 interview that lasted about 45 minutes. The questions were all just standard behavioral ones, nothing difficult. I received a call a day or two later letting me know I had been selected for a final round interview. There was a dinner reception and then you either interviewed the next day or the day after that. The final round interview consisted of four 30 minute interviews, two with finance managers and two with the people who run the program. Again, just standard behavioral questions for the most part. They got back to candidates within a few business days to let us know if we had gotten an offer.
If you plan on applying for this position, just be aware that you'll be competing for spots with people who have already interned there. It seemed like most of the current FLDPs had interned there previously, so I really felt like I was at a disadvantage having not done so.