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The refactored instance of Blueshift will be email centric meaning there will always be a one to one relationship with emails and profiles in Blueshift. The customer id will in the new your refactored instance is made up of the profile key which will be included by default as a URL parameter. This profile key (pk) is comprised of the affiliate id and email address which is MD5 hashed. The profile key can be passed back as the customer_id to tie an event back to a user profile with out needing to decode the vid2 value.
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