USE master;

DECLARE @last_role TINYINT;
SET @last_role = (
   SELECT TOP 1 [replica_role]
   FROM [dbo].[replica_role]
);

DECLARE @current_role TINYINT;
SET @current_role = (
   SELECT ROLE
   FROM sys.dm_hadr_availability_replica_states
   WHERE is_local = 1
);

IF (@last_role = 2 AND @current_role = 1)
BEGIN
    USE SSISDB;
    OPEN MASTER KEY DECRYPTION BY PASSWORD = 'x'
    ALTER MASTER KEY ADD ENCRYPTION BY SERVICE MASTER KEY
END

USE master;
UPDATE dbo.[replica_role] SET [replica_role] = @current_role;

The target database ('SSISDB') is in an availability group and is currently accessible for connections when the application intent is set to read only. For more information about application intent, see SQL Server Books Online.