Hi,
First post here - been a lurker for a while, but thought I'd register to reply to this message.
I'm in the same boat as you, except my courses finish this October. I wanted to the STP with the NHS this year - but as mentioned, the degree classification isn't revealed until December. I enquired with the administration team who organise the STP and they said they need a firm result for application to the programme. I also looked in to applying for graduate schemes, in particular with Jaguar Land Rover (where my wife works) and they would accept applications with provisional results. So I think it's down to the individual employer/university who will be accepting you. The best thing to do is to write to the university you are looking at for Postgrad study and explain the situation to them - they will then be able to give you the options available to you.
For me, I'm trying to get work experience as the STP will start in October 2014, but the application process starts in January 2014. Getting work experience in the field I'm interested in will hopefully show them I'm serious about what I am applying for.
Hope that helps!
Phil