I think what you are experiencing might just be the wifi reconfiguring itself as you make changes.
- If your desktop is connected via ethernet to the Beryl, you might try configuring the Beryl from the desktop.
- When the wifi of the Beryl reconfigures itself (as it would do if you are connecting to the ee), the wifi signal stops for a time. Your phone sees that, and then connects to whatever else it finds. You should “forget” that network, or set it to not autoconnect, so that the phone doesn’t do that, and waits for the Beryl to come up again. After you are done setting up the Beryl you can revert those settings.