It's quite usual to use extension number as the trigger of call flows. Cisco, Avaya, even Genesys on-premise products, all of them support this, why PureCloud can only support E.164 number as trigger?
If a call flow is used inside a corporate only, the flow of course doesn't need and should not have a E.164 number.
And in a brown-field migration, those internal extension numbers have been published and used as trigger number for long time, so it's not possible to change. In this case, a lot of efforts are needed to do translation. Another issue is the arbitrary E.164 numbers used are not allocated by PTT, so it might and will conflict with some E.164 numbers of PTT and cause those numbers can't be reachable by PureCloud users.
#Routing(ACD/IVR)------------------------------
Wen Gu
SITA SCARL- Switzerland Branch
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