A reliable source told me that he is testing the 16-35mm f/4.0 FE lens that will be announced on March 22. The lens shows quite some distortion when used wide open. But he can live with this because the lens is very compact and otherwise delivers very good optical quality.
He also doesn’t know yet when the 24-70mm f/2.8 GM II lens will be announced (but it should be coming very soon).