Resignation Approval workflow issue

In resignation approvals If the Line Manager (LM) does not take any action on a submitted request within 20 days, the approval should automatically escalate to the second level approver (HR Specialist) without requiring the LM’s approval. Could you please advise if this behavior can be achieved through BPM Worklist configuration (such as deadlines and expiration policies), or if any alternative approach is recommended ?

Approval Hierarchy: LM—>LMs LM up to Director Level—>HR