A 79-year-old woman with long-standing type 2 diabetes, mild dementia, and multiple comorbidities including heart failure and chronic kidney disease has an HbA1c of 7.0 percent on low-dose basal insulin and metformin. She has experienced two episodes of severe hypoglycaemia in the last 6 months. According to Diabetes Canada, which HbA1c target is most appropriate for her?