I had a situation where my PRI line was in a major fire where 1700 lines were burnt and was unable to make calls for over a week. To avoid this in the future I was thinking of configuring twillo sip service as a backup. What exactly would I need to do to configure this? The SIP trunk would be inactive until the PRI went down and then I would have to change the config to move over to twillio. The phone numbers would not be the same but I could also have the CO redirect our numbers to the twillio ones if need be.
Thanks in advance!