dmertens
The sim assessment could be on either the A320 or the B757. At the last intake, as far as I'm aware, they required crew for both types, I think out of the six or so candidates that made it through four went on to TR on A320 and two on the B757. They will allocate the TR once the successful candidates have been chosen.
I was told told that out of the many thousands of online applicants only 40 or so made it through to be called up for interview and assessment, so if you're at this stage you must be doing OK.
The procedure may have changed since the last Pilot Platinum scheme was run so I guess things may not go as I have described.
One of the aspects of SEP/MEP flying they may ask about is: have you a factual story to tell about your own flying experience(s) from which you have learned something important. It could be something during a SEP/MEP flight that maybe you should have reported but didn't think it was necessary!!
I do hope you get through. Correct me if I'm mistaken but they are looking, like most airlines, to increase their intake of female pilots. You stand a good chance as long as you haven't had any ATPL theory and/or IR failures during your training.