You are lucky. Enphase is switching the API with a firmware update. When that happens, this will break. You can find some more info here: [New Binding] Enphase Envoy Solar System gateway - #151 by jswim788
If you have it working now, I would be tempted to block the Enphase Envoy’s access to the internet to keep it working. Unfortunately their app won’t get updates if you do that. I have no idea if/when they will upgrade all customers or not. It seems to be random as to when this upgrade is pushed out.
After their firmware “upgrade” I had to open a support ticket to get access again. Once I did that I was able to get data from the Envoy via a Python script as mentioned in the above post.