"Delete Snapshots" are not adhering to the retention days

Products

• VMware vCenter Server

Issue/Introduction

VM snapshot chains are being deleted prematurely, before the retention period specified in the 'Delete Snapshots' setting. The current behavior is resulting in a critical failure to preserve snapshots for the specified retention period.

This occurs in the following workflows: 

1. Scheduled task Delete Snapshots with Retention days via vSphere client 

2. Delete All snapshots with the retention days for the VMs which are hosted on ESXi versions earlier than 8.0.3 from vSphere client. 

Environment

This issue manifests only when VMs are running on ESXi versions lower than 8.0.3 and the vCenter server version is at least 8.0.3

Cause

From ESXi 8.0.3 and later, the existing API "vim.VirtualMachine.removeAllSnapshots" was modified to support optional parameter "SnapshotSelectionSpec" which has retentiondays in it. 
Hence, when vCenter 8 U3 communicates with ESXi hosts older than 8 U3, the optional parameter is stripped out. 
The "removeAllSnapshots" then executes in the older context, thus removing all snapshots.

Resolution

Broadcom Engineering is actively investigating and working to resolve this issue.
However, an ETA for the fix is not yet available.

Additional Information

References:

Create a Scheduled Task

How do I Schedule Tasks for Snapshot Deletion