It's now something you have to plan in advance. Local rules may vary but the pub they were showing us on the news last night expects you to ring ahead and book a table and a time slot. No-one is allowed to stay for more than three hours.
If you make it through the door you'll be obliged to give the management your name and contact details.
You'll then be shown to a table- and expected to stay put. It's unlikely you'll be allowed to go up to the bar. You certainly won't be permitted to stand at it.
Am I so desperate for beer that I'm prepared to deal with all these restrictions?