I did stage 2 yesterday, and it lasted from 1 till about 4, so 3 hours long. So you'd probably be done by 12:30ish. The last part of the stage is tests, and different people work through them at different speeds, and you're free to go as soon as you're done, so the end time does fluctuate a bit!
Does anyone else have stage 3 on 3rd October?