Reporting error in publication after copyright transfer
This is a question (or series of questions) for the editor. You can ask what they intend to do beyond taking down the online version. Ask if you can provide a correction (assuming that is possible). Ask if there is anything else you can do.
And an email &quot;yesterday&quot; won't get a response for a while.
But look for some mutually acceptable outcome.
I don't think the copyright transfer has any bearing on this, actually, other than that they have the responsibility now.