I have two SQL servers Standard Edition with a basic Always ON availability group.
I have updated the server to Enterprise Edition. But i can't upgrade existed availability group from basic. The checkbox "Basic Availability Group" is not accessible 
I have two SQL servers Standard Edition with a basic Always ON availability group.
I have updated the server to Enterprise Edition. But i can't upgrade existed availability group from basic. The checkbox "Basic Availability Group" is not accessible 
It includes this point:
Basic availability groups cannot be upgraded to advanced availability groups. The group must be dropped and re-added to a group that contains servers running only SQL Server 2016 Enterprise Edition.
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