Hi There,
Yes, Azure Virtual Desktop (AVD) is supported via the ExpressRoute Microsoft Peering connectivity model.
In your scenario, where the Philippines delivery centre connects via an ExpressRoute circuit to an ExpressRoute Gateway in Azure Cloud Singapore/Japan, managed by a CSP partner, and then to the Azure AVD solution hosted in the same regions, this configuration is supported. ExpressRoute provides the necessary connectivity to ensure seamless access to Azure AVD.
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