I have purchased a used IPK (not IPKII) phone system that was previously used with only 2 incoming POTS lines and a fax, but I have 3 POTS lines and a fax.

Whoever set it up previously programed the call arrival keys on the DTH-8D IPK Dterm 80 like this:
buttons 1 and 2 show incoming calls. And can be used to access outside lines to make clls. button 3 is used to page "all". and button 4-8 are extension buttons.
We have no need for a paging function. And
I need to change that button (3) to show calls incoming on line 3. Currently, when line 3 rings the phones light up indicating that a call is coming in on the 3rd line. But we can not pick it up. Also, we cannot choose that line to make outgoing calls. (Because that button is set to "Page")

If this change is a system programming change and requires a tech visit, I would like to know if there is a key sequence that would allow me to pick up that line or use it to make outgoing calls until I get a tech in here?

Thanks
Mike