I don't think it's a "replace Robin" mentality. It's more a showing more characters we've never really seen before. As mentioned before Katana has history with Bruce, as part of the Outsiders, a team he personally handpicked and led. "The Batman" first paired Bruce with Babs and then eventually introduced Robin. It could be the case with "Beware The Batman" as well. It's just too early to tell since it just started.
The design of Alfred seems to have changed as well since the promo pic was released. He for some reason reminds me of Bob Hoskins. This is clearly based on Geoff Johns version from Earth One. He still functions the same...he just has more to bring to the overall picture.