Trying to use the powershell command Set-AzAppServicePlan to upgrade a App Service Plan from Standard S1 plan to a Standard S3 plan. There doesn't seem to be a way to define the "S3".
Set-AzAppServicePlan -Name $appServicePlanName -ResourceGroupName $resourceGroupName -Tier "Standard" -NumberofWorkers 1 -WorkerSize "Small";
I've tried all manner of different values in the "-Tier" param such as "StandardS3" or "StandardV3" and it always defaults to "Standard S1"