The GOM is well-named, I am not planning on relying on it - I have purchased an OVMS kit (got a message that it was shipped to me on Friday) so that I can have access to the % SOC, which I have heard is easier to work with as a guide to remaining capacity/range. My iPhone is also set up to show %SOC, so I am used to working with that.
GOM changes depending on mode selection and driving pattern/history, among other factors. It is always nice to see something close to the advertised number, but I am trying not to be too invested in what it is saying. I have had my ZS EV for just on a month, and I had surgery 2 weeks ago so I have not been doing that much driving, and my daily commute is about 25-30km, so I am charging about once a week, once it is down to around 30%.
Best of luck with it all!
My surgery was to my bottom - I am a bit jet-propelled myself at present.