For unit 1 the best thing to do is just relax at this point do some past papers and don't let it get the better of you and try and stay calm about it. As long as you know the case studies and know your exam technique then you will be alright. I say this from experience as last year I let this exam control my life by trying to know every single word of the spec in a last minute panic. It's not worth the panic just know your case studies and know how to apply it to the questions and you'll be alright. (I'm an A2 resitting and I did this for the resit mock and aced that)