But as mentioned they must have 4 digits and 5 digits and should enable call between them.

According to your opinion, Can you tell us the best solution? if we must apply 4 digits and 5 digits as mentioned in this senior.

Hi Gavinr98,I have the same scenario and i did this to solve it: Create Partition: (4digit) , (5digit)Create Calling Search Space: (4digit_to_5digit) add the Partition (5digit), (5digit_to_4digit) add the Partition (4digit)  4 digit = XXXX ,  Create ...