Stage 1
Hi Kimberley
I passed stage 1 a couple of months ago, you should have a rough idea of which type of plane goes on which type of journey but you really won't need to go into much more detail than that, as for preparation, outside reading the booklet you've been sent there is not much more you can do so from a personal point of view I would say that is plenty of time.
Just try and relax on the day and don't feel to down if things don't seem to be going your way, plenty of people have said in the past that they think they've failed but have actually went onto pass. (including myself at stage 2!!)
Good Luck