Hello WebMaster,
To scale down, go to Azure web application and select Scale up (App Service plan). The selected pricing tier will have a blue border around it. Change the lower pricing tier based on your requirements. Click on Select.
The effects on your Wordpress site would be measurable based on the different services of Premium V2 vs Standard, for example High Availability, Network bandwidth, max active connections, storage... etc. Make sure the Standard plan details match the needs for your Site before downscaling.
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