Working with multiple simultaneous host connections within TTerm for iPad is simple.
Open a first connection to your host system in the normal fashion, by tapping the connect button on a saved connection item.
While connected and on the terminal screen you'll see a button at the top left of screen labelled Connections. Tap this button to return to the saved connections list. This will return you to the list of saved connections and retain the connection to your host system.
On the connections screen the button on the connection(s) currently open will be labelled connected rather than connect. To return to an open session at any time, simply tap the connected button.
To open a second (third, fourth, etc) session tap the connect button of any other saved connection.