That is a load of rubish. The hard and fast rule in the UK is 8 hours bottle to throttle. But however (and it is a big however) each airline will have different rules. My airline reccommends 10 hours bottle to throttle with only MODERATE drinking in the preceding 24 hours. When away on 'trips' you are governed by the country that you are in and you have to be very careful. Parts of Scandanavia are so strick that you may as well not bother drinking at all. The UK limit for blood alcohol is about 1/10th of the drink driving limit, and I am told that there is only an allowance at all to take into account the natural body alcohol that occurs in all of us. It is very a judgement call as everyone reacts differently, there have been pilots prosecuted after a couple of glasses of wine with dinner the night before report, others seem to be able to down 10 pints and be o.k in the morning. The best advice is just be sensible, you will learn your own limits very quickly, and don't drink to the numbers as some do. I have seen some say 'I can drink 5 pints as the human body processes 1 unit of alcohol per hour and I have 10 hours to report' this is a dangerous way to act becuase that is such a generic statement.