The value for the HbA1c has always been in
percent (%) in the USA.
I guess that it all depends on what country you are in. If he was giving you the value in IFCC-HbA1c (mmol/mol) then 41 mmol/mol is slightly less than DCCT- HbA1c at 6%. Where: IFCC-HbA1c (mmol/mol) = [DCCT-HbA1c (%) - 2.15] × 10.929.
I hope the information helps.