First, a disclaimer: I doubt that any of these initial candidates will pan out. Striking gold the first time we pan for it seems unlikely; we'll likely need to both refine the process and develop even more powerful, refined instruments.
But, I think this is a superior way to conduct SETI research. The truth is, in order for a civilization to be advanced enough for us to find them across the vast distances involved, they're likely going to need to be able to construct Dyson structures.
Now, whether we want to attract the attention of a species so advanced is another question (interestingly, one I'll be talking about on a panel at MisCon next weekend!). But we should definitely be looking!
“A Study Suggests We Found Potential Evidence of Dyson Spheres—and Alien Civilizations”: https://www.popularmechanics.com/space/deep-space/a60780331/dyson-sphere-evidence-alien-civilizations/
“For more than half a century, scientists have wondered if searching for technosignatures like Dyson Spheres from super-advanced civilizations could help us discover intelligent life elsewhere in the universe.
Two new studies analyze data from star-gazing satellites to develop a framework for eliminating false positives or potential natural explanations in that search.
Each study found evidence that a handful of stars among the millions observed contain excess radiation that’s consistent with potential Dyson spheres and can’t be immediately explained away as a natural phenomenon.”
And if you want to deep-dive into the science of this research, here’s a piece on the always excellent and thoughtful Centauri Dreams blog: https://www.centauri-dreams.org/2024/05/18/seven-dyson-sphere-candidates/