When multi-line calling, there's no way to switch between the different calls. Often times the first pickup is a voicemail or answering machine, while the other lines are still ringing. After dispositioning the Voicemail pickup, I'd like to be able to connect to either of the other calls in progress. If one happens to get answered by a live person, I have to wait for that call to conclude, then call the person back in the hopes that they answer again.