The data within Freeagent belongs to you. You can request that Freeagent set up the billing to you directly and remove from the accountants dashboard. If you email support@freeagent.com they should be able to assist.
They'd be justifiably concerned about a potential conflict of interest and may ask for you to sign a contract to that effect, not work for a competitor, etc. However unless you sign such an agreement, you're not obliged to supply a list of clients, e.g. I wouldn't be allowed to provide you with a list of clients, even if some may well be in competition (possible, never know), I know there are other considerations but I'm sure you get the gist.
