Back in the 1980s, we were called into the squadron for a station minival - I had had a couple of beers and yet was put on the flying program to fly in two hours time. I told the captain that I was unfit to fly due to having had a beer within the prohibited time limits and suggested that he take someone else. Next morning I was called into my flight commanders office for a hats on b*ll*cking and read the riot act about squadron loyalty. I did ask about what support I would have if there had been an incident and I was given a blood test etc but this was sniffed off with the comment that this would not happen.
On the same squadron (now AWACS), but over 15 years later, I was placed on six hours to deploy as Christmas standby for personnel in theatre. I pointed out that I was on leave. That's all right said the flight commander - you can do this while on local leave. I then pointed out that I could not drink over the Christmas period and that if I was on leave then I could not be on standby - if he signed the leave cancellation then I would do the standby and then take my leave over the new year. After a stand-off we finally agreed a compromise to change the standby to a 24 hour commitment as he wanted me to deploy in the new year (it was during a period when mission crews were deploying for about 4 weeks in every six due to a manning shortfall - the squadron had declared too many crews for the number of mission personnel but to quote the Squadron boss - he "could not reduce the number of crews because it could affect the crew captain's career").
The bottom line - there are rules for drinking, but they only apply to the individual - the squadron hierarchy could ignore them. (Perhaps this post should be on the "Just Culture" thread).