Amar is 40 years old and he is a lorry driver. He is asymptomatic and has just been diagnosed with Type 2 Diabetes Mellitus. He has been informed that he does not need medication at this stage and is keen to make significant lifestyle changes. He has no other past medical history and recent visual assessment was normal. You have a telephone consultation with him in which he is enquiring whether any driving restrictions may apply.
What is the DVLA restriction period (if any) for him?