Hi @Rav ,
Thanks for reaching out.
It is not possible to implement polling in Azure AD B2C custom policy.
However, the decision to allow user to wait long during sign/sign in is bad user experience and create lot of challenges when user abort/close the session.
A better approach would be to let the user sign-up/sign-in to the application and execute whatever is needed on the application side before giving the user final access.
Hope this will help.
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