This document explains how the approval process expiration works.
The approvals remain pending until the "Deny Expired Approval Processes" APM runs.
The "Deny Expired Approval Processes" cancels any approval process for a pending enrollment or external learning request. If the requested event has a start date that is in the past. The process sends a notification to the user confirming the denied request using the ApprovalProcessRequestExpired or ApprovalProcessRequestDenied notification templates.
You can configure the Deny Expired Approval Processes by going to System Admin > Automatic Processes > Deny Expired Processes.
Note: Currently there is an Enhancement request that is under consideration, since when a user registers for a training with an approval process and the supervisor or whoever is meant to approve does not do so in time the approval expires and then the system takes the "wrong" approval supervisor.
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