Yes, the fix are part of 5.0.0.
Besides, I know you’ve been interested in call blocking and worked on a solution. With 5.0.0, will also come a call blocking function. It’s integrated in the UI, but it also provides an API for third party applications. You can register an application (with the proper rights) as a call filtering application. Then, on an incoming call, the voicemanager is broadcasting it over D-Bus, as normal, but postpones the ringing (and UI reaction) until it receives back a filtering approval over D-Bus. I don’t remember what I put, maybe something like one second or two as a grace period before the voicemanager let the incoming call pass through anyway if no filtering application is answering.