I passed Stage 2 in January, I was on one of the first dates and I've still heard nothing regarding Stage 3 so I've been sending the odd email but not been told much.
In regards to the confusion about Stage 3 & 4 and all the stuff that people are talking about above me, I asked Claire who was running the Stage 2 tests when I was there and she said the last stage is Stage 3 and then a medical so I'm not sure quite how outdated the infographic is, a few other people who have already been through NATS have told me that Stage 3 was the last stage for them as well.