wanted to enrich myself with more information on the phrase ‘behind bar’, the answer to the clue of 1a, particularly as far as the first definition was concerned and went on to explore the net. While getting to know about the role of the landlords and other bar staff in serving their customer, I also came across a time period that is tagged as a ‘lock-in’.  It is the period when an owner or a landlord of a pub that is a public house allows patrons to continue drinking in that pub after the legal closing time, on the theory that once the doors are locked, it becomes a private party rather than a pub. Patrons may put money behind the bar before official closing time, and redeem their drinks during the ‘lock-in’ period, so as to make possible that no drinks are technically sold after the closing time. The origin of the British lock-in was a reaction to the changes that happened in 1915 in the licensing laws in England and Wales, which curtailed opening hours to stop factory workers from turning up drunk and harming the war effort. From then until the start of the twenty-first century, the licensing laws of the United Kingdom changed very little, retaining these comparatively early closing times and the tradition of the ‘lock-in’ system.
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