What is the difference between simple multipoint and the advanced multipoint that TK30 supports? 

TK30 supports advanced multipoint, enabling two handsets to remain connected to TK30 so that you can manage calls on both handsets. For example, this allows you to answer a call on handset #2 while you are already in a call on handset #1. The call on handset #1 is put on virtual hold, while you talk on handset #2. In the case of simple multipoint, when you answer a call on handset #2, the Bluetooth connection to handset #1 is dropped.