fboesch Let us know how it goes.
According to this article, Sunrise should already have the necessary infrastructure in place. So I guess it’s just a matter of updating the carrier profile on IOS.
However, it’s also possible that Sunrise was just partnering up with Google and uses Google’s Jibe Cloud to offer RCS services (so all the RCS messages are routed through Google’s servers and only works between Android phones). Apple probably is not keen to partner up with Google as they normally do the bare minimum. It would also be questionable in terms of data protection and privacy.