Microsoft announced plans to build out the Indonesia Central region with Availability Zones in 2021. Unfortunately, there is not an updated ETA or project timeline that can be shared. You can read the announcement here. Updates will be posted to the Azure updates RSS feed page.
Sorry that I cannot provide more details. We are glad you are excited about using this region. If you are looking for a nearby region, I recommend exploring the services available in the Southeast Asia region.
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