Under the form tab > form name there is an aside that says “Note: the sender email address is: ‘no-reply@webforms.io’.” This is not correct.
I have clients with forwarding rules to route form responses to different emails using no-reply@webforms.io as the incoming sender trigger. Not sure when it was changed to no-reply-forms@webflow.com (client suspects May 2017), but I learned of this from a client complaint.