I do ZRH-LCY-GLA twice per year, normally. The transfer time on the Friday evening option is 30 minutes (exactly the MCT). The aircraft is (usually) always the same, with the same crew positioning north. Once time, we were late out of ZRH and I said to the Purser if they could wait on me to complete formalities to be back on the same aircraft. They waited for me, and I was last to board.