updating

Author: dstagnol

pages/hosted_private_cloud/hosted_private_cloud_powered_by_vmware/vmware_maintenance/guide.en-gb.md

@@ -174,9 +174,12 @@ To get the details of each robot, run the following API call:
 
 | Purpose | Reason | Preventive instructions | Impact | Estimated duration | Frequency |
 |---------|--------|-------------------------|--------|--------------------|-----------|
-| Update of Zerto virtual machines (Zerto Virtual Manager, VRA) to the latest version offered by OVHcloud. | Zerto lifecycle of OVHcloud. | None | The Zerto console is unavailable\* during the maintenance. During that period of time, all the related zerto operations can't be performed (failover, VPG management, etc.).<br><br> - VRA is redeployed so that replication is interrupted and the RPO increases momentarily. | 01H30 | Based on the publisher lifecycle |
+| Update or migrate Zerto virtual machines (Zerto Virtual Manager, VRA) to the latest version offered by OVHcloud. | Zerto lifecycle management by OVHcloud. | A **health check report** may be sent if issues are detected before the maintenance, requiring resolution before it can proceed. | - **Upgrades**: Minimal impact, temporary unavailability of replication and failover.<br>- **Migrations**: Full service downtime, requiring reinstallation on a new platform. | **Upgrades**: ~1h per instance.<br>**Migrations**: Up to 12h per instance. | Based on the publisher lifecycle |
 
-\*: see explanations below.
+> [!primary] 
+> **Difference between upgrades and migrations:**
+> - **Upgrades** involve updating existing Zerto components (e.g., Zerto 10u6 to 10u7) with minimal service disruption (~1 hour).
+> - **Migrations** involve transitioning to a new platform (e.g., from Windows-based Zerto to appliance-based Zerto 10u6), resulting in up to 12 hours of complete downtime.
 
 ### Glossary