yesterday I got locked out my pfsense box, so I went to the console, opened the shell and typed a
to disable the firewall. It did not work, and looking at the pftop I saw that there were still connections being blocked by the firewall. No matter how many time I repeated the command or typed a flush on all rules, the firewall was always active. The only way I found to disable it was using the developer console. Now I'm guessing if the filter is somewhat automatically reloaded by some kind of event (e.g., squid proxy running or what) so that the console actions are vanished by the automatic filter reloading.
In my case I locked out because I removed an interface from the menu while the filter still had references on it (I thought the filter would have update itself but apparently it was not).