How do i set proxy for the GhostDriver (PhantomJS) at the fly?

Question

I'm trying to change a proxy every time I reload a page in GhostDriver(PhantomJS).

Everything what i found was set the proxy at the launch time:

DesiredCapabilities capabilities = new DesiredCapabilities();
        capabilities.setCapability(PhantomJSDriverService.PHANTOMJS_EXECUTABLE_PATH_PROPERTY, "FULL_PATH_TO_PHANTOMJS");
        capabilities.setCapability(PhantomJSDriverService.PHANTOMJS_CLI_ARGS, new String[]{
                "--proxy-auth=login:password",
                "--proxy=proxy:port",
                "--proxy-type=proxy_type"
        });

        WebDriver driver = new PhantomJSDriver(capabilities);

But is it possible to change the proxy at the fly?