Requesting / being provided access to a user's email

My app requires on-going access to a users email to look for and pull in certain information coming from a specific source(s), which may come many times in a day. To extent I can find anything related to being allowed to access email, the direction seems to be (paraphrasing) "it's allowed if the user provides permissions". see App Store Review Guidelines and it's related 5 sections on Safety, Performance, Business, Design, and Legal. see link - https://developer.apple.com/app-store/review/guidelines/#introduction
Does anyone know if Apple has any prohibition against this kind of access and data pull or if it is prohibited in any way. I can't find anything definitive on the subject.
thanks
Requesting / being provided access to a user's email
 
 
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