Marston's Fast Cask will go into every Pitcher & Piano bar plus any sites that take the brewer's new EPA brand.
Fast Cask — a revolutionary new method of storing cask beer in pub cellars — has been very well received since its launch during Cask Ale Week, said category manager Justin Way.
"Camra's endorsement — or at least a lack of campaigning against it — has been really good news for us," he said.
The concept allows beer to drop bright almost immediately, which means it can be served from upright casks that can be moved around at will.
It therefore eradicates the age-old problem of casks being knocked down in crowded pub cellars, followed by a delay until the beer drops bright again.
The process is currently being rolled out to Pitcher & Piano sites as a programme of re-furbishments for the sites is completed.
"We have also had pubs in the freetrade signing up for Fast Cask, and these are pubs which have never had cask before," said Way.
Fast Cask was initially available for two beers: Marston's Pedigree and Wychwood Hobgoblin, but it is now also available
for Marston's EPA brand, which was launched on St George's Day.
"EPA is a new product and it will only be available in Fast Cask, whereas the others are also available in a conventional format," says Way. "Because of this we think it should be a lot easier to encourage trial of Fast Cask via EPA."