Management operations and hardware gen experience

Improved article with the impact of changing hardware generation and maintenance window. Updated table with this scenario.
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cc: @urosmil

Author: urosmil

articles/azure-sql/managed-instance/management-operations-overview.md

@@ -59,7 +59,7 @@ The following tables summarize operations and typical overall durations, based o
 |Operation  |Long-running segment  |Estimated duration  |
 |---------|---------|---------|
 |First instance in an empty subnet|Virtual cluster creation|90% of operations finish in 4 hours.|
-|First instance of another hardware generation in a non-empty subnet (for example, first Gen5 instance in a subnet with Gen4 instances)|Virtual cluster creation<sup>1</sup>|90% of operations finish in 4 hours.|
+|First instance of another hardware generation or maintenance window in a non-empty subnet (for example, first Premium series instance in a subnet with Standard series instances)|Virtual cluster creation<sup>1</sup>|90% of operations finish in 4 hours.|
 |Subsequent instance creation within the non-empty subnet (2nd, 3rd, etc. instance)|Virtual cluster resizing|90% of operations finish in 2.5 hours.|
 | | | 
 
@@ -70,12 +70,16 @@ The following tables summarize operations and typical overall durations, based o
 |Operation  |Long-running segment  |Estimated duration  |
 |---------|---------|---------|
 |Instance property change (admin password, Azure AD login, Azure Hybrid Benefit flag)|N/A|Up to 1 minute.|
-|Instance storage scaling up/down (General Purpose service tier)|No long-running segment|99% of operations finish in 5 minutes.|
-|Instance storage scaling up/down (Business Critical service tier)|- Virtual cluster resizing<br>- Always On availability group seeding|90% of operations finish in 2.5 hours + time to seed all databases (220 GB/hour).|
-|Instance compute (vCores) scaling up and down (General Purpose)|- Virtual cluster resizing<br>- Attaching database files|90% of operations finish in 2.5 hours.|
+|Instance storage scaling up/down (General Purpose)|No long-running segment|99% of operations finish in 5 minutes.|
+|Instance storage scaling up/down (Business Critical)|- Virtual cluster resizing<br>- Always On availability group seeding|90% of operations finish in 2.5 hours + time to seed all databases (220 GB/hour).|
+|Instance compute (vCores) scaling up and down (General Purpose)|- Virtual cluster resizing|90% of operations finish in 2.5 hours.|
 |Instance compute (vCores) scaling up and down (Business Critical)|- Virtual cluster resizing<br>- Always On availability group seeding|90% of operations finish in 2.5 hours + time to seed all databases (220 GB/hour).|
 |Instance service tier change (General Purpose to Business Critical and vice versa)|- Virtual cluster resizing<br>- Always On availability group seeding|90% of operations finish in 2.5 hours + time to seed all databases (220 GB/hour).|
-| | | 
+|Instance hardware generation or maintenance window change (General Purpose)|- Virtual cluster creation or resizing<sup>1</sup>|90% of operations finish in 4 hours (creation) or 2.5 hours (resizing) .|
+|Instance hardware generation or maintenance window change (Business Critical)|- Virtual cluster creation or resizing<sup>1</sup><br>- Always On availability group seeding|90% of operations finish in 4 hours (creation) or 2.5 hours (resizing) + time to seed all databases (220 GB/hour).|
+| | |
+
+<sup>1</sup> Managed instance must be placed in a virtual cluster with the corresponding hardware generation and maintenance window. If there is no such virtual cluster in the subnet, a new one must be created first to accommodate the instance.
 
 **Category: Delete**