Hi Vaun,
If you are looking at adding Standard Edges to an existing on premise model then you can do this in a single org but they must be configured against a different site. Site A can have your existing Mini Edges connected, Site B would have the standard Edges which you can then do testing against by adding SIP trunks etc. When you come to cut over the services it's a simpler transition.
Adding this link below the shows acceptable combinations of Edges, and highlights the site controls to allow different types of Edges within a single org.
https://help.mypurecloud.com/articles/edge-redundancy/------------------------------
Gareth James
CALLSCAN AUSTRALIA PTY. LTD.
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