The limit is the limit is the limit. There is no excuse for being over the limit. In this case it would have taken 4 more hours to be under the limit, thats half again the 8 hour rule!!!
I suspect that this is a case of last nights alcohol not cleared, the 1 hour 1 unit is only a guideline as food, excercise, sweating in a sauna etc all have effects but if he has had 8 hours off that is 8 units (approx) metabolised which is 4 pints plus another 4 units not metabolised thats 6 pints of medium strength beer.
I know that this thread is filled with "tee totallers" which I find highly unlikely, I have never met a tee total pilot ever, so lets be honest, 6 pints on a night out is not a huge amount. Some wouldn't even be visably drunk on that. Way way too over the limit to drive and definately too much if you are flying early the next day.
We all like a nightstop , a bit of a room party with the cabin crew, it is one of the perks of the job but as someone said earlier the 8 hour rule alone is not enough. Work out how much is legal then add a couple of hours on to be sure, I know of one airline that has a 10 hour rule others that are 12 hours, all depend on moderation of course. In this case another 4 hours (12 total) probably would have seen him under the limit. Not saying that he would be fit to fly , fatigue wise etc though.
If crews see the 8 hours as a target almost, ie drink up to 8 hours and stop that won't save your bacon.
Having said that 48 hours is ridiculous, drinking alcohol in moderation while strictly obeying the limits is not a crime.