Bigga, I'm in a similar situation to you. I had the 'congratulations and maybe' email after going to the assessments in London, and then I told them I'd rather go to the 2nd group in Oct/Nov instead of the end of August.
I also emailed them about a month ago to ask for the exact dates, and they confirmed them to me saying 'please wait and we will give you the full details as soon as it's arranged'. That gives the impression that I
am through, despite the maybe bit from before...