My suggestion is to plugin in a spare phone into the new jack. See if it comes up with an existing configuration on that TN. If it has keys assigned, you can look it up with prt DNBs. If you see any lights flashing, you know its at least cross connected. If nothing happens -- no sounds, no lights, the jack is not cross connected.
If you find a set programmed on the new jack's TN, move this set (or OUT it if you are 100% certain it is not needed) to an unused TN. (LD 20; REQ: LUVU; TYPE: (phone type) to find an unusned TN). This will free up the TN of the new jack.
Now you can do a MOV of the phone from its current TN to the TN you just freed. In LD 11, you can do MOV to move the phone from one TN of the set to an unused TN.
REQ: MOV
TYPE: 2616 (or 3904, etc)
TN loop shelf card unit (where the phone is now)
TOTN l s c u (TN where you want the phone to reside)
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