In order to manage all the activities and stored values / infos for every single user should be good having a General (as I named in the title: SuperUser_ID) which will be able to syncronize all the data coming from different channels evaluating them and communicate (back) with an “all-known” responses.
Right now you have the Contact ID and the ability to merge contacts.
Wouldn’t the current Contact ID be the super ID you’re looking for
Right now you have the Contact ID and the ability to merge contacts.
Wouldn’t the current Contact ID be the super ID you’re looking for
Well, you mean as I’ll merge (or create an automatic merging flow) under that contact ID (which is the Messenger’s contact ID CUF) I’ll be able to see e.g. the bot will be able to see all the CUFs belong the particular user and use it?
Actually I never tried the merging contacts 
during the 8 years I’ve spent within :-)
So you can automatically merge (up to a point).
If you start a contact on a channel, then add other channels, then the profile will be automatically merged to a Contact ID (for example, start with IG, then add Email, SMS, WhatsApp and Telegram - these could all be merged).
Where it becomes trickier is IG + Messenger, where, most of the times, you’ll end up doing a manual merge.
As for your question, you can’t create an automatic merging flow, but you can add as I mentioned before and have them merged.
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