DeletionPolicy:Snapshot cannot be specified for a cluster instance, use deletion policy on the cluster instead

I am trying to create RDS cluster and aurora instance using the cloudoformation template below:

{
      "AWSTemplateFormatVersion" : "2010-09-09",

  "Description" : "example setup",

  "Parameters" : {
    "DBInstanceIdentifier" : {
      "Type": "String",
      "Description": "Name for the DB instance."
    },
    "DBUser" : {
      "Type": "String",
      "Description": "Master user"
    },
    "DBPassword" : {
      "Type": "String",
      "Description": "Pass"
    },
    "DBModel" : {
      "Type": "String",
      "Description": "Instance model to be used for the DB."
    }
  },


  "Resources": {
    "RDSCluster": {
      "Type": "AWS::RDS::DBCluster",
      "Properties": {
        "MasterUsername": { "Ref" : "DBUser" },
        "MasterUserPassword": { "Ref" : "DBPassword" },
        "Engine": "aurora",
        "DBClusterParameterGroupName": "default.aurora5.6",
        "VpcSecurityGroupIds": [{"Fn::GetAtt" : [ "DBFromSiteSecurityGroup" , "GroupId" ]}]
      }
    },
    "AuroraInstance": {
      "Type": "AWS::RDS::DBInstance",
      "Properties": {
        "DBInstanceIdentifier": { "Ref" : "DBInstanceIdentifier" },
        "DBParameterGroupName": "default.aurora5.6",
        "Engine": "aurora",
        "DBClusterIdentifier": {
          "Ref": "RDSCluster"
        },
        "PubliclyAccessible": "true",
        "DBInstanceClass": { "Ref" : "DBModel" }
      }
    },

    "DBFromSiteSecurityGroup" : {
       "Type" : "AWS::EC2::SecurityGroup",
       "Properties" : {
          "GroupDescription" : "Enable MySQL",
          "SecurityGroupIngress" : [
             {"IpProtocol" : "tcp", "FromPort" : "3306", "ToPort" : "3306", "CidrIp" : "195.171.102.98/32"}
          ]
       }
    },
     "DBFromSiteSecurityGroupIngress1" : {
         "Type" : "AWS::EC2::SecurityGroupIngress",
         "Properties" : {
             "GroupName" : { "Ref" : "DBFromSiteSecurityGroup" },
             "IpProtocol" : "tcp",
             "ToPort" : "3306",
             "FromPort" : "3306",
             "SourceSecurityGroupName" : { "Ref" : "DBFromSiteSecurityGroup" }
         }
     }
  }
}

The db_model parameter I am passing is "db.t2.medium". The cluster gets created successfully in the cloudformation console however the AWS::RDS::DBInstance creation fails with the following error

"DeletionPolicy:Snapshot cannot be specified for a cluster instance, use deletion policy on the cluster instead." 

What's more weird that when I try to run the same CF template in say eu london region, it works fine!!! Is there something wrong with the EU ireland region and aurora?