I thought maybe the fructosamine test might be an alternative then read this.
"What is Fructosamine?
Sugar (glucose) in the blood tends to stick to proteins. Fructosamine is formed when a sugar and a protein (usually albumin, but also globulin, or lipoprotein) are combined [1].
Similarly to HbA1c (glucose + hemoglobin), fructosamine is a measure of the amount of glucose in the blood. However, while HbA1c measures your 3-month average glucose, fructosamine reflects mean blood glucose over the previous 2-3 weeks. This is due to the shorter life cycle of albumin [1, 2].
The advantage of fructosamine over HbA1c is that it’s not affected by changes in red blood cells and hemoglobin caused by anemia, blood loss, or nutrient deficiencies [1].
That said, there are also drawbacks to using fructosamine. Temperature, vitamin C, bilirubin, urea, and total protein levels can all affect fructosamine levels. All conditions that increase or decrease albumin levels will also affect fructosamine [1, 3].
Fructosamine tests will not be a good measure of blood sugar control and should not be used in people who have [1, 3, 4, 5]:
thyroid disease
intestinal disease (protein-losing enteropathy)
kidney disorders (nephrotic syndrome)
liver disease
increased immunoglobulin levels (especially IgA)
Fructosamine is used less often compared to HbA1c, mainly because it’s not standardized and it’s less reliable than an HbA1c test. In addition, because there is considerable overlap between the ranges of healthy people and diabetics, it can’t be used to screen for diabetes"
https://labs.selfdecode.com/blog/fructosamine/