If I'm not mistaken, the XN120 is the UK version of the Aspire. With the Aspire, you can do a "Trunk-to-Trunk" forwarding using the service code 835, followed by the trunk port (e.g., trunk 1 = 001), select the time mode (e.g., 2 = night), then enter the number to be forwarded to, then [HOLD]. The Aspire programming is:
11-10-06, 11-10-07, 11-10-08, 20-06-01, 20-07-05, 24-04-01.
However, that is my least favorite way of forwarding.
The BEST way to do achieve after hours call forwarding is to utilize the telephone company's "call forwarding" feature....... the customer has to subscribe to it on a per line basis.....
locally, here, when I want to forward my office number to my cell phone, I press line 1, dial the telco's call forwarding code: *72, then dial my cell. When I answer my cell phone, the call forwarding is activated.