edits for readability

Author: dlepow

articles/api-management/upgrade-and-scale.md

@@ -6,16 +6,19 @@ author: dlepow
 
 ms.service: api-management
 ms.topic: how-to
-ms.date: 09/08/2022
+ms.date: 09/14/2022
 ms.author: danlep
 ---
 
 # Upgrade and scale an Azure API Management instance  
 
-Customers can scale an Azure API Management instance by adding and removing units. A **unit** is composed of dedicated Azure resources and has a certain load-bearing capacity expressed as a number of API calls per second. This number doesn't represent a call limit, but rather an estimated maximum throughput value to allow for rough capacity planning. Actual throughput and latency vary broadly depending on factors such as number and rate of concurrent connections, the kind and number of configured policies, request and response sizes, and backend latency.
+Customers can scale an Azure API Management instance in a dedicated service tier by adding and removing units. A **unit** is composed of dedicated Azure resources and has a certain load-bearing capacity expressed as a number of API calls per second. This number doesn't represent a call limit, but rather an estimated maximum throughput value to allow for rough capacity planning. Actual throughput and latency vary broadly depending on factors such as number and rate of concurrent connections, the kind and number of configured policies, request and response sizes, and backend latency.
 
 [!INCLUDE [premium-dev-standard-basic.md](../../includes/api-management-availability-premium-dev-standard-basic.md)]
 
+> [!NOTE]
+> API Management instances in the **Consumption** tier scale automatically based on the traffic. Currently, you cannot upgrade from or downgrade to the Consumption tier from a dedicated service tier.
+
 The throughput and price of each unit depend on the [service tier](api-management-features.md) in which the unit exists. You can choose between four dedicated tiers: **Developer**, **Basic**, **Standard**, **Premium**. If you need to increase capacity for a service within a tier, you should add a unit. If the tier that is currently selected in your API Management instance doesn't allow adding more units, you need to upgrade to a higher-level tier.
 
 >[!NOTE]
@@ -37,17 +40,15 @@ You can choose between four dedicated tiers: **Developer**, **Basic**,  **Standa
 
 * **Basic**, **Standard**, and **Premium** are production tiers that have SLA and can be scaled. For pricing details and scale limits, see [API Management pricing](https://azure.microsoft.com/pricing/details/api-management/#pricing).
 
-* The **Premium** tier enables you to distribute a single Azure API Management instance across any number of desired Azure regions. When you initially create an Azure API Management service, the instance contains only one unit and resides in a single Azure region (the **primary** region. 
-    Additional regions can be easily added. When adding a region, you specify the number of units you want to allocate. For example, you can have one unit in the **primary** region and five units in some other region. You can tailor the number of units to the traffic you have in each region. For more information, see [How to deploy an Azure API Management service instance to multiple Azure regions](api-management-howto-deploy-multi-region.md).
+* The **Premium** tier enables you to distribute a single Azure API Management instance across any number of desired Azure regions. When you initially create an Azure API Management service, the instance contains only one unit and resides in a single Azure region (the **primary** region).
+
+    Additional regions can be easily added. When adding a region, you specify the number of units you want to allocate. For example, you can have one unit in the primary region and five units in some other region. You can tailor the number of units to the traffic you have in each region. For more information, see [How to deploy an Azure API Management service instance to multiple Azure regions](api-management-howto-deploy-multi-region.md).
 
 * You can upgrade and downgrade to and from any dedicated service tier. Downgrading can remove some features. For example, downgrading to Standard or Basic from the Premium tier can remove virtual networks or multi-region deployment.
 
 > [!NOTE]
 > The upgrade or scale process can take from 15 to 45 minutes to apply. You get notified when it is done.
 
-> [!NOTE]
-> API Management instances in the **Consumption** tier scale automatically based on the traffic. Currently, you cannot upgrade from or downgrade to the Consumption tier from a dedicated service tier.
-
 ## Scale your API Management instance
 
 ![Scale API Management service in Azure portal](./media/upgrade-and-scale/portal-scale.png)
@@ -72,7 +73,8 @@ You can choose between four dedicated tiers: **Developer**, **Basic**,  **Standa
 If you're scaling from or to the Developer tier, there will be downtime. Otherwise, there is no downtime. 
 
 ## Compute isolation
-If your security requirements include [compute isolation](../azure-government/azure-secure-isolation-guidance.md#compute-isolation), you can use the **Isolated** pricing tier. This tier ensures the compute resources of an API Management service instance consume the entire physical host and provide the necessary level of isolation required to support, for example, US Department of Defense Impact Level 5 (IL5) workloads. To get access to the Isolated tier, please [create a support request](../azure-portal/supportability/how-to-create-azure-support-request.md). 
+
+If your security requirements include [compute isolation](../azure-government/azure-secure-isolation-guidance.md#compute-isolation), you can use the **Isolated** pricing tier. This tier ensures the compute resources of an API Management service instance consume the entire physical host and provide the necessary level of isolation required to support, for example, US Department of Defense Impact Level 5 (IL5) workloads. To get access to the Isolated tier, [create a support request](../azure-portal/supportability/how-to-create-azure-support-request.md). 
 
 ## Next steps