@davidyapp You’ve got me worried about you! Here’s why:
This discussion is about when to take fast acting insulin at meal time (eg before or after the meal). Members (including you) responded that lots of people take a combination of long acting and fast acting insulin. This is typical and a commonly prescribed treatment method.
What concerns me is your reference to “Dexcom meter” that you later refer to as “sensor/system” and that “if it shows an A1C of 6.9…..” I use a 15 day Dexcom G7. The Dexcom doesn’t show A1C. The data shows the glucose in your interstitial fluid and compares pretty well to what your blood sugar is, allowing you to keep an eye on things 24/7.
You mention basing your fast acting insulin dose on the Dexcom data and sited examples of 6-8 units, 12-15 units, 20 units, 24 units, 28units. Are you talking about per meal or per day? Could you please clarify? I hope you mean per day because the range of units you mention (6 - 28) seems like an awful lot per meal IMHO! Please let me know. Thinking about you! (The discussion is about when to take fast acting insulin at MEAL time.)