May I ask something pls?

[matainta]

This functionality allows incoming calls from your land-line (PSTN) connected to the OBi110 to be answered by Auto Attendant, and thus allowing the caller to make a new call via ITSP (for lower termination rate).
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[drgeoff]

Correct.  But bear in mind that there are now two calls.  One between the caller and the OBi110 and one between the OBi110  and callee.  Either or both of those may incur call charges.