This is the reply I got from them

Does Campbell work for them it has more spin and bull dodo than a politician could even make up

Thank you for taking the time to contact us regarding Stella Artois.
Over the past five years, we have noticed a fast-growing demand for lower strength beers. Our skilled brew masters have already responded by developing a range of new beers with different levels of alcohol content. These include Stella Artois 4% one of the fastest growing lagers in pubs and bars across the country. And more recently we launched Stella Artois Black (4.9% ABV), a beer that is matured for longer for a rich and full bodied taste.
Now, our brewers have used all their skill to carefully brew Stella Artois with a slightly lower alcohol content. It is still brewed using the original Stella Artois yeast and celebrated Saaz hops but most importantly of all, it still has the same full, flavour and clean crisp taste, confirmed through rigorous testing by our expert tasters and consumers. It is just that its ABV is now 4.8% instead of 5%.
We are very proud of our beer and our heritage which is part of 600 years tradition in Leuven, Belgium. Six centuries of brewing beer has taught us that consumer tastes do change. And we continue to brew high quality beer that meets the tastes and needs of our consumers.
We hope this helps you understand what we have done and why we have made these changes. We always welcome feedback from our consumers so if you would like more information or have any questions please contact us at consumer.helpline@ab-inbev.com
Thanks again for contacting AB InBev UK.
Kind regards