wifi.clearCredentials() not appearing to work with 0.7.0-rc.4

Troubleshooting
1

I am having trouble with the following that was working fine with 0.7.0-RC.3 and now on 0.7.0-RC.4:

            statusMessage("Clearing Stored WAP Credentials");               //V066 immediate feedback in case .hasCredentials takes time
            if (WiFi.hasCredentials())      //button press is valid to clear credentials
            {
                timer3.start();
                if (WiFi.clearCredentials())
                {
                    statusMessage("All WAP Credentials Cleared");
                    Particle.disconnect();
                    WiFi.disconnect();
                    isTriedConnectOnce = false;         //to ensure when reconnecting that particle connect is called once
                    WiFi.off();
                    WiFi.on();
                }
                else 
                {
                    statusMessage("Error - WAP Credentials Not Cleared"); //did not work!
                }
                int i = WiFi.hasCredentials()?13:0;
                mainButtons(0, i, 3, 4);
                connectionSymbol();
                hangOn(2000);
                clearStatusLine();
                footerScreen(param.itemName);
            }
            else  statusMessage("No Stored WAP Credentials");

This handler for a button to clear the wifi credentials appears to work except WiFi.hasCredentials() returns true. Any ideas what might be happening?

UPDATE: I couldn’t see why this was returning true to WiFi.clearCredentials() and true to WiFi.hasCredentials() immediately after. I thought I would try the same binary on a different photon. Hey presto - it works. A firmware load issue!!