The parameter updateIndex

[MarkYQJ]

Based on spec.,

Retrieving a Work Order Receipt Update
...
Inputs:
...
updateIndex is an index of the update to retrieve. Value "0xFFFFFFFF" is reserved to retrieve the last received update.

However, the receipt chaincode is implemented as below

func (t *Receipt) workOrderReceiptUpdateRetrieve(stub shim.ChaincodeStubInterface, args []string) pb.Response {
...
    // If updateIndex value "0xFFFFFFFF" is reserved to retrieve the last received update.
    if arg2 == 256 {
...
    }

256 looks like a wrong index value?