Cisco Single Number Reach is a pretty neat feature. However, apparently you can’t have the box pull calls back for delivery into the local VMB if you are using POTS connections.
Here is the lab on SNR on the UC500 platform.
I ran into an unexpected issue with SNR that it would be great to see explained in the lab. If you are using POTS lines into FXO ports on your UC box and using an external number for the mobility destination (e.g. a cellphone), then the system will NOT be able to pull the call back in and send it to the CUE voicemail. On a cellphone, the call will end up in the remote voicemail if unanswered.
Relevant section from document:
Call forwarding of unanswered calls, configured with the cfwd-noan keyword in the snr command, is not supported for PSTN calls from FXO trunks because the calls connect immediately.