The Red channel
During my working life I had to go through the Red channel because I had goods on carnet.
Since I've retired, and Brexit, I still go through the Red channel. There are fewer people passing through and more staff, and although I know my Class C drug (Zolpidem, on prescription) can go through the Green channel, I also know that the people staffing the Red channel are more knowledgeable and will process me quicker. I keep the tablets in my pocket and show them, they look them up on the database and nod nod through you go, It's a lot slower when you go through the Green channel, there are crowds and the staff aren't as knowledgeable. If you get stopped for a random check you can be there ages.