You may be aware that we're working on a revamped PI Notifications. PI Notifications 2016 includes fundamental changes to how PI Notifications work. As such, our goal is to provide a migration tool from PI Notifications 2012x to PI Notifications 2016. However, due to the nature of a custom delivery channel in that you could've basically done anything , I would really love to talk to you to understand what your custom delivery channel does and how our migration tool may impact your custom delivery channel.
Please contact us via: BetaPINotifications@osisoft.com