David,
In one of the organizations I worked for there were two sets of BA's - IT BA's called Business Systems Analyst and Finance BA's simply called BA's.
The work of an IT BA is pretty well understood here, so I'll focus on the work done by our counterparts in Finance. Obviously, it involved a lot of Financial Reporting, Sales Trend Analysis, Forecasting, Price Increase simulation and its effect on the bottom line etc. In almost all cases, they would rely on adhoc reporting provided by the IT BA's (myself). These were not standard reports and were usually bespoke, meant to be only used once, but in some rare cases they may be asked for repeatedly, in which case they were eventually turned into part of the Standard Reporting set.
Having said that, over time, I realised, due to indepth discussions I would have with my Finance counterparts, I understood what they were doing well enough to assist then with overly complex reporting needs. In one recent case, while being unemployed and searching for work, I was even considered for the role of a Finance BA. It makes sense for a IT BA to transition to a Finance BA, but in the long run, without the necessary Accounting/Financial Management background, I don't know if the career will be fulfilling or provide necessary growth.