Problems with sugar disregulation, start way way before it shows in blood tests. What you were eating was only a problem because like all of us, your system was having problems handling the Glucose. That's why you gain weight, you cannot use the fuel properly, so your body has to store it away.
With the changes you've made, i would expect your next test to be below prediabetic level, so no diagnosis, BUT you clearly now have problems with carbs, so the new regime is for life, if you want to continue to avoid diabetes.
Well done, and keep up the good work.