How Do I Deactivate/Remove Remote Processing?

I’d like to undo/remove the API key I obtained from phpList.com and entered into my site via:

http://www.mysite.com/lists/admin/?page=hostedprocessqueuesetup

I revisited the above link but there’s no option to actually delete or remove the key.

Tried searching for the API key in both config files but no luck.

Is this Remote Functionality controllable/editable from the web admin console, the config files or some combination of both. Is the configuration form accessible by manually using the above URL also available from the admin console?

@tcb I think that you need to add this to config.php, then when you process the queue there will be a choice of using the remote processing

define('SHOW_PQCHOICE', true);

https://resources.phplist.com/system/config/show_pqchoice