Is this really that hard to enough people that it can be a thing twice a year? If so I think a lot of people need to look seriously at their alcohol intake.
I had a colleague who did this last year who made it seem like the hardest thing she'd ever done, and I just didn't understand it. We work 12 hour shifts 6.30-6.30 both nights and days. Presumably it's not hard to not drink the day before your 06:30 start, or during the day before your 18:30 start. Hopefully most of us aren't going home at 06:30 to crack open a beer, and having done it myself I'm amazed anyone has the energy after 4 12 hour shifts to crack open the beers.
By that rational we spend most of our time not drinking, why is it so hard to further extend that?