Gave a thought to this and a solution what i have in mind is to insert file name and location in a table while genrating the file (BCP) and then ssis should query that table pickup the file name and path and ftp it to the required location.
You can wholly design this logic using a script task using .NET code can do this for you. Also you ca use a combination of Script task to read file name and assign the name to SSIS variable and later use an Execute SQL task to insert values in a table and again use a Script task to FTP the file while reading the file name from a table.
Raunak J