Hi @Bo Huang
As of now, we do not have the information on the exact date for the preview or general availability of the Mexico region in Azure. Azure datacenter/infrastructure concerned division didn't announce any specific ETA for GA/Preview for the Mexico datacenter region yet.
I recommend keeping an eye on the Azure updates page or subscribing to the Azure blog for the latest news and updates on the Mexico region's availability. You can also contact Microsoft support for more information.
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