I am trying to make a large BLE sensor network, hypothetically anywhere from 20-100 devices in a STAR configuration. I see there is a 20 max limit on concurrent connections. Does that mean I can only have 20 paired devices or can I have X number of devices paired, but only 20 connection within that moment. For example. If I am posting a message once every 30 seconds or 1 minute, I wouldn't have much overlap in TX messages from each end node. I was looking into the ANT+ profile but the range is short and I want the largest range BLE can take me. I also want to have ACK packets and possibility to do OTA firmware upgrades.
So I guess, when building a large network, what is the true definition of "concurrent connection" and what is the recommended way to build a large network with infrequent single packet messages?