I guess we were not clear on the reason for your post, which seemed to be concern about your blood sugars. Have you been diagnosed with pre-diabetes? At 87 I would feel fine about an A1C above what you have, to be honest. If fluctuations affect how you feel, avoiding fast carbs/sugar and having protein and/or fat with carbs helps, as do frequent small meals.

I am dealing with fluctuations myself at 72. My kid was diagnosed with type 1 diabetes at age 4 so have been dealing with blood sugars for 30 years! I am terrible about avoiding sugar: it causes lows for me two hours later.