Is SFB Bot framework also in preview for tenants operated by 21vianet

Greetings,

Could anyone help confirm if SFB Bot framework also in preview for tenants operated by 21vianet?

According to the bleow link, it should be under preview stage for global tenants:

https://msdn.microsoft.com/zh-cn/skype/Skype-For-Business-Bot-Framework/docs/overview?f=255&MSPPError=-2147217396

However, it does not mention if it supported for tenants operated by 21vianet. Per my test, it seems not supported becuase when I initiate the below cmd, an error is generated:

New-CsOnlineApplicationEndpoint -ApplicationID 41ec7d50-ba91-1208-73ee-136b88859725 -Name NameOfTheBot -Uri sip:username@yourdomain.com

Cmdlet invocation error

    + CategoryInfo          : NotSpecified: (:) [New-CsOnlineApplicationEndpoint], CmdletInvocationException

    + FullyQualifiedErrorId : Error processing cmdlet request,Microsoft.Rtc.Management.Hosted.PlatformService.NewPlatf

   ormServiceAppEndpointConfigCmdlet

    + PSComputerName        : admin0g.online.partner.lync.cn

Business Voice Directory service discovery failed. Please try again at a later time.

    + CategoryInfo          : NotSpecified: (Microsoft.Rtc.M...t a later time.:PlatformServiceCmdletException) [New-Cs

   OnlineApplicationEndpoint], BvdCmdletException

    + FullyQualifiedErrorId : Could not instantiate TrustedApplicationEndpointManager,Microsoft.Rtc.Management.Hosted.

   PlatformService.NewPlatformServiceAppEndpointConfigCmdlet

    + PSComputerName        : admin0g.online.partner.lync.cn