Interesting. I remember there was a brightness concern with the satellites reflecting too much light, but assumed it was all ok because IIRC they hit their reflectivity reduction targets.

However, this seems to be about transmissions from the satellites interfering with non-visible observations.

In a study, published in the Astronomy & Astrophysics journal, scientists used a powerful telescope in the Netherlands to observe 68 of SpaceX's satellites and detected emissions from satellites are drifting out of their allocated band, up in space.

... "Why this matters is because of the number," Dr Di Vruno said. "Suppose that there is a satellite in space that radiates this kind of signal, there is a very, very small chance that this satellite will be in the beam, in the main site, of your telescope."