First of all, congrats on the position.  Without knowing how your bank works, it's impossible for me to tell if this will be a more technical role or not.  However, in the banks in my area a 'Business Analyst' role is seldom about being the conduit between IT and business.  In fact, they use that title to describe someone who plays a supporting role in the accounting/finance department by generating budgets, forecasts, reconciliations, etc.  If anything, I'd be wary that it leans towards that type of job if anything.

That said, this may just be a local phenoma (Western Canada), so if I were you I would ask your future supervisors what the primary duties of your role will be.  It doesn't hurt to ask, and I bet they would like to see you take the initiative and show an interest in learning what you'll be doing before you start.

Good luck.