You’ve got time. If they’re just in the stages of announcing the cast, it means that they’ve also only just begun production. Chinese dramas don’t have the same live-shoot drama system as SK does, it films/edits everything before a drama airs, which means that the EARLIEST that this drama will be released is ~ March/April of 2020. At the same time, with the new regulations in place due to government censorship, it might be even longer than early 2020 before the drama airs