Upon receiving an invite via email from a FreeStyle LibreLink user, do I have the option to skip the

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Upon receiving an invite via email from a FreeStyle LibreLink user, do I have the option to skip the sign-in process upon LibreLinkUp installation and do that later?

No, you must create an account or sign into an existing account, then accept the invitation from the Freestyle LibreLink user before you can view their glucose data.  The system has to recognize the connection, which is based on the email address of the person who was invited.