I read up a bunch on this yesterday, and am feeling pretty mixed about the autoimmune development! On the one hand, better understanding of what we're dealing with would be immense, and - particularly if they can develop a test off the back of this - the relief of stigma and validation that this could mean for fibro sufferers will certainly be welcome.
On the other hand, autoimmune diseases are notoriously difficult to treat, and are generally considered impossible to cure. Many are managed with steroids and anti-inflammatory medications, or immune suppressants like chemotherapy drugs. My mother has a rare autoimmune disease called birdshot chorioretinopathy that is gradually blinding her, and she's been running this gamut for some time now with a range of unwelcome impacts.
My understanding is that steroids have already been tested quite a bit for fibro, with not great results - and the side effects are grim with lasting consequences. I suspect we have to hold out hope for some entirely new treatment developments, even if the autoimmune connection sends research in new directions. Here's hoping!