OP, you were asking me before for help, so here's what I know.
From what I understand, the course structure for first year BA Psych students should look something like this:
Autumn Session:
2 BA Core Units (Contemporary Society & Texts and Traditions)
Psych Unit (Human Behaviour)
Elective Unit (Can be chosen from any area, given that it is offered at level 1, and is at your home campus, or else a rule waiver will need to be filled out. Check the handbook for a list of units you can choose)
The elective I chose is called Inventing Modernity, which is of the Humanities and Languages discipline. Sounds shite, but all the good electives are offered at Bankstown and Parramatta, and I'm at Penrith.
Spring Session:
2 BA Core Units (Australia and the World & Analytical Reading and Writing)
Psych Unit (Behavioural Science)
Elective Unit (Same as for Autumn Session)
You might want to check the BA core units, though, as the teaching periods at your campus might be different to what I've listed (as I mentioned before, I'll be at Penrith).
For the Psychology submajor, I know that first year students cannot enrol in it, because I checked the handbook, and all the units for this submajor are at level three, as well having assumed knowledge and/or prerequisites.
Here's a quick link:
Handbook- Bachelor of Arts
Check for yourself everything I've mentioned