Knowing if a peer disconnected

Hello,

When using js-libp2p, and listening for peer:disconnect events on libp2p.connectionManager I could not see the event when loosing network connectivity (at least within the first minute).

What should be my expectations around this? Is it driven by a timeout? I am especially interested in mobile environment where network or connection can be lost due to poor signal or switch from one network to another (wifi<>cell).