2 is added before next numbers

2õ-õõ-õõ
4õ-õõ-õõ
5õ-õõ-õõ
7õ-õõ-õõ
9õ-õõ-õõ

4 is added before next numbers

3õ-õõ-õõ
6õ-õõ-õõ

For numbers beginning with 1,
there is a special rule

from 11-00-00 to 11-79-99 add 2
from 11-80-00 to 12-49-99 add 4
from 12-50-00 to 12-99-99 add 2
from 13-00-00 to 17-99-99 add 4
from 18-00-00 to 18-99-99 add 2
from 19-00-00 to 19-99-99 add 4

City telephone code has changed from 8312 to 831

Cell phone numbers remain the same