I found the same bug when testing in Australia, but found a work around:
I tried using the local number format but with double zero instead of single zero, when adding the number to the user group. For example if you want to allow phone number 0411111111 then add number 00411111111 to the user group. This worked for me (even though this is technically an incorrect phone number). The router allowed the number to be saved in the user group, and it recognised the incoming call that had the single zero in the number, eg. 0411111111 . Problem solved.