Following our migration to the new stack over the last few months, effective from 2000 on Wednesday 7th February 2018 the remaining hostnames resolving to the deprecated stack (e.g. those containing "deprecated.simwood.com") will be retired and will no longer resolve. Additionally, any calls sent to the former old stack IP addresses will fail.
Together with this, the "beta" endpoints will be removed as previously advised, therefore it is imperative to ensure you are not using hostnames with "beta" in the domain to ensure uninterrupted service.
This work was originally scheduled for 1st February 2018 (see http://blog.simwood.com/2017/12/new-voice-stack-live/ for more information) but was since delayed due to other operational considerations, effectively giving a full additional week to migrate traffic if you have not already done so.
Inbound calls may arrive from any of the signalling IP address contained within the interop, therefore it's critical that all these IP addresses are permitted.
The vast majority of customers have been using the "new stack" since December 2017, and will be unaffected by this change. In the unlikely event you do experience any issues, please see the article above, and contact the Operations Desk who will be happy to assist.