In Projects, once a project has been created and then requested, it then needs to be routed for approval. Once an employee has been selected as an approving manager, it is up to that employee to approve or reject it, or else it is stuck in that state.

If that employee is unavailable for whatever reason (left the organization, no longer in the same role, on vacation, or hit by a bus), that project can not be actioned on.

I can think of a few solutions to this,

1. Provide a function like Assign Substitutes like in the Maintenance and Service Desk modules.
2. Provide a task/view in the Projects' Approve process that will allow editing of the approving manager(s) after a certain number of days as specified in an application parameter.
3. Provide a task/view in the Projects' Approve process that will allow editing of the approving manager(s) as long as none of them have approved it yet.