444-0000 would be described as a phone number, and the ext 1234 is a DN you can arbitrarily assign.
If you wanted 444-0000 to always ring at ext 1234, then you identify the "Trunk Route" that number is a member of. In other words, when calls come in, what series of numbers are displayed on your phone. The first series is probably 4 digits long and then a ' - ' (dash) then a shorter series of numbers.
LD21
REQ prt TYPE rdb - press return responding to CUST and ACCD. The first series of numbers displayed in the phone is the ACCD.
Then LD21 REQ prt TYPE ltm
The second series of numbers will be one of the members.
The after you determine how many other trunks are in a hunt chain, you can decide how many extensions are needed to handle the calls.
Then create a new LD16 Trunk Route with everything the asame as the one you printed, except respond YES to AUTO.
Out the trunks you want to point to ext 1234 then rebuild them as members of your new Route, and responding to ATDN with "1234"
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