 The plan further proposes that the US would use either 00 or 11, while Canada would use the other, in order to allow customers to distinguish countries by use of these digits, which do not appear at the beginning of the 12-digit number.This distinction would quickly vanish as digits other than "0" and "1" are used in these positions after permissive dialing ends.Under this proposal, the "N9X" format NPA codes, which are currently reserved from assignment, would be released and be available for normal assignment for code relief and other purposes.