incorrect error message on "build index" for an already built/online gsi index.

1. create index with defer_build=true - success
cbq> CREATE INDEX ind2 ON default(SequenceNumber) USING GSI WITH `

{"nodes": ["127.0.0.1:8091"], "defer_build": true}

`;
{
"requestID": "0b2e42f0-aa11-4989-9f90-23536c135829",
"signature": null,
"results": [
],
"status": "success",
"metrics":

{ "elapsedTime": "88.194851ms", "executionTime": "87.418092ms", "resultCount": 0, "resultSize": 0 }

}
2. build index =-- success
cbq> BUILD INDEX ON default(ind2) USING GSI;
{
"requestID": "275e2ffb-8dbf-476a-bb7b-948e026aa49c",
"signature": null,
"results": [
],
"status": "success",
"metrics":

{ "elapsedTime": "475.899839ms", "executionTime": "474.950418ms", "resultCount": 0, "resultSize": 0 }

}

3. select * from system:indexes – shows the index is online

cbq> select * from system:indexes;
...

{
"indexes":

{ "datastore_id": "http://127.0.0.1:8091", "id": "4e91a5c226a8ca28", "index_key": [ "`SequenceNumber`" ], "keyspace_id": "default", "name": "ind2", "namespace_id": "default", "state": "online", "using": "gsi" }

},
4. accidentally issue build index again,the error message should be "index already online/built" or so, instead it displays the index is not in Ready state.

cbq> BUILD INDEX ON default(ind2) USING GSI;
{
"requestID": "7cb10bf6-c117-4d8a-b902-71fdd782a493",
"signature": null,
"results": [
],
"errors": [

{ "code": 5000, "msg": "BuildIndexes - cause: Index ind2 is not in READY state." }

],
"status": "errors",
"metrics":

{ "elapsedTime": "22.994577ms", "executionTime": "22.086024ms", "resultCount": 0, "resultSize": 0, "errorCount": 1 }

}

I assume this is a incorrect error and not actual state of index, since I get the right results on further queries using the same index. example below.
cbq> explain select * from default where SequenceNumber=252;
{
"requestID": "6f2b5509-ff4d-451e-8a22-9c9bf0077f8a",
"signature": "json",
"results": [
{
"#operator": "Sequence",
"~children": [
{
"#operator": "IndexScan",
"index": "ind2",
"keyspace": "default",
"limit": 9.223372036854776e+18,
"namespace": "default",
"spans": [
{
"Range":

{ "High": [ "252.000001" ], "Inclusion": 1, "Low": [ "252" ] }

,
"Seek": null
}
],
"using": "gsi"
},
{
"#operator": "Parallel",
"~child": {
"#operator": "Sequence",
"~children": [

{ "#operator": "Fetch", "keyspace": "default", "namespace": "default" }

,

{ "#operator": "Filter", "condition": "((`default`.`SequenceNumber`) = 252)" }

,
{
"#operator": "InitialProject",
"result_terms": [

{ "star": true }

]
},

{ "#operator": "FinalProject" }

]
}
}
]
}
],
"status": "success",
"metrics":

{ "elapsedTime": "73.602244ms", "executionTime": "72.807628ms", "resultCount": 1, "resultSize": 2022 }

}