You can renumber the voice mail ports to somthing out of the range, so that you can recover those 2 digit numbers.

Lets see, 70 2 digit extensions would run from 10 through 89. That only leaves 9 for ARS. You have NOWHERE to go with all the leftovers like lines, calling groups, paging, etc. etc.

You're going to have to put the system in setup space, and then renumber them back to 3 digit exensions, in a range like 100-199, keeping the last 2 digits the same as the original 2 digit extension numbers.

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