I agree lash egg...
https://the-chicken-chick.com/salpingitis-lash-eggs-in-backyard/
In my experience.. a gal can lay regular eggs in addition to these lash eggs.. If you can identify which hen you MIGHT be able to treat with antibiotics. Ultimately prognosis is eventually poor.. but how long is hard to say.
Please note, I dispatch (euthanize) hens once salpingitis is identified since it is a symptom of internal infection and chickens do everything they can to hide their discomfort until they no longer can. Since the reproductive tract get removed, we still harvest the meat if viable or send to another family if my own is too emotional over their attachment to said bird to consume despite knowing euthanasia was the right choice for us.
Hope they still thrive!