We use AWS Backup via a policy set at the AWS Organizations level (in the management account).
I now want to expand the policy to cover the af-south-1 (Cape Town) region, but that region is not offered from the 'Backup plan regions' dropdown. If I instead edit the JSON, adding af-south-1 causes an error: 'The provided policy document does not meet the requirements of the specified policy type.'
I am aware that the af-south-1 region is opt-in. I have already opted it in at the management account and all member accounts where it is used.
AWS Backup itself is available in af-south-1.
Anyone seen this themselves, or know the reason for it ?
<edit> the accepted answer covers the reason - thanks, I hadn't spotted that.