I can't seem to find a way to email users about their overdue review assignments or unclosed reviews. Is there a way for an administrator to schedule a weekly notification to team leads or individuals regarding their outstanding reviews in crucible?
According to this document, Crucible should automatically send reviewers a reminder email one working day before the deadline.
Maybe Preset Reminders are what you're looking for? But this must be configured for each review, meaning that it's currently impossible to configure a batch process to run on a weekly basis on all your reviews at once in order to send reminders.
As far as I see, this is not ideal for you, so I have created a new issue in our development issue tracker to ensure our development team is aware of what you need:
I would suggest adding any comments to the issue above as well as voting on the issue to create it's popularity and likelihood of being implemented in a future release.
For more information on how Atlassian implements new features and improvements please see the following document:
My apologies that we don't have a solution for you at this time.