I am also dealing with a similar issue. Accounts User with permission for a cost center is able to view P&L / financial data for whole company - as std P&L report by default loads with “blank” filter on Cost Center. The default accounts dashboard loads with a P&L graph that shows company wide profitability- even for a user restricted to a branch cost center. This is a serious breach of confidentiality imo - a user is able to escape their permission - by default.
Dont know how to resolve. Branch accounts dept should have access to branch P&L / P&L report.