If you have an active phone numbers on the Sideline service and want to port it to Ring4, you can request a phone number transfer to Sideline.
1- Here is the Sideline for the port-out: https://support.sideline.com/hc/en-us/articles/214737083-Porting-your-number-out-of-Sideline
2- Create a Ring4 Business account: go to www.ring4.com and open the console
3- Request the port-in of the number: Fill the Ring4 porting form
The porting process can be immediate or last up to 2-5 business days.
To learn more about Ring4, visit www.ring4.com