Confidence: I'm as sure as I can be.
Notes: I am not going to get into any discussion about common names of lichens, which for the most part are not "common", in the sense of being equivalently understood by different people. Where they exist they are likely to have been made up by a recent book writer and will only be understood by other readers of the same book. One of the red Cladonia spp. (floerkeana) does have a much older and established British name of "Bengal Matchsticks" and in America is called "Gritty British Soldiers", but this isn't it. But anyhow, I am not going to be drawn into any such discussion ... (oops!) ... and for a difficult genus like Cladonia I am going to use nothing but the precision of the Latin name. So, yes, C. diversa, characterised by wide, often slightly irregular cups, commonly with large, bright red apothecia, corticate granules within the cups, squamulose exteria (not so visible here) and overall yellow-green colour. One of the commonest of the red-fruited species here in Britain and Ireland, but largely confined to the oceanic fringe of Europe.