There seem to be few probiotic supplements that are backed by any research at all. Worse, tests by consumer organisations/ the media have found that some brands do not have anything like the strength (measured by CFUs) on the label. How the product is transported and stored after manufacture is relevant.
One of the regulars here (GrahamSPhillips) is a pharmacist and has listed a few brands of probiotics – including VSL3 and Symprove – that have been studied in specific populations.
Clever Guts emphasises eating a really wide a variety of live fermented, probiotic rich foods for a really wide variety of species of gut friendly bacteria and yeasts. It is encouraging that, after having their guts flushed out for science, both Dr Michael Mosley and Prof Tim Spector turned to whole and fermented foods, not supplements.
I have needed 5 or 6 courses of antibiotics in a year, which has decimated my gut microbiome! I eat a range of traditional aged European cheeses (unpasteurised milk/ blue veined/ mould ripened/ rind washed) PLUS Nexabiotic brand capsules (claims 23 strains, 34.5 billion CFUs).
The worst gut symptoms after a course of antibiotics was when I fed the surviving microbes a massive dose of sugar, the best when they got oily fish, vegetables, berries, seeds and so on.
Is your gastroenterologist or registered dietician supporting you with Clever Guts, ideally by going through your food and symptom diary regularly? My concern would be how balanced and varied your diet is, given the restrictions of coeliac disease + time pressures + Clever Guts + personal/ family tastes.