Cannot resize Azure VM due to Accelerated Networking being enabled

 You decide to drop the size of a D series Azure VM to B series and are told it's incompatible with Accelerated Networking, perhaps you don't care.

Here's how to disable Accelerated Networking, no reboot required!

In Azure Portal, find the relevant info for your VMs 'network interface name' and 'resource group name', use those in place of the <placeholders> and run the command in Azure CLI from the icon in the top-right of the portal. 

Your VM will continue to run and will not drop the network connection. Once the command has completed you can resize your VM.

az network nic update --accelerated-networking false --name <network interface name> --resource-group <resource group name>