The legal limit is 35. Two pints of beer would get you up to that, so he either had three pints or had more but the alcohol was going out of his system. Today was an initial plea hearing, he won't have given a reason today, just stated whether he was guilty or not guilty as it wasn't a full trial.
If he pleaded guilty then he would have lost his licence immediately. If he goes not guilty then he only gets banned at the point of conviction, so he can keep driving in the meantime.
It could simply come down to that. He might not live in Sheffield and has to travel far to the Lane and Shirecliffe. Maybe he's planning to move to the area so pleaded not guilty so that he make the arrangements in the interim before pleading guilty on the day, or change his plea prior to trial.
Lots of people play the system when it comes to keeping their driving licences for a bit longer until found guilty.