Repliconnect expense question

I am doing some expense reporting in Excel, with data pulled via Repliconnect API. We are on Gen2.

One of my queries looks like this:

[
  {
    "Action": "Query",
    "QueryType": "ExpenseByArguments",
    "DomainType": "Replicon.Expense.Domain.Expense",
    "Args": [
      null,
      null,
      null,
      {
        "__type": "Date",
        "Year": 2018,
        "Month": 8,
        "Day": 1
      },
      {
        "__type": "Date",
        "Year": 2018,
        "Month": 8,
        "Day": 31
      },
      null,
      []
    ],
    "Load": [
      {
        "Relationship": "User",
        "Domain": "Replicon.Domain.User"
      },
      {
        "Relationship": "Entries",
        "Domain": "Replicon.Expense.Domain.ExpenseEntry",
        "Load": [
          {
            "Relationship": "Project",
            "Domain": "Replicon.Project.Domain.Project",
            "IdentityOnly": true           
          },
          {
            "Relationship": "ExpenseType",
            "Domain": "Replicon.Expense.Domain.ExpenseType",
            "IdentityOnly": false
          }
        ]
      }
    ]
  }
]

The idea is to pull all expense entries (with project IDs and user info) for expenses incurred in a given date range. Based on the query documentation, this is what this should do. 
However, what I am seeing is that it is pulling entries tied to expense sheets with an expense sheet date (where is that in the UI? creation date?) in the date range, and I am seeing expense entries out of range (e.g. including late July).

Is the only way to query based on Incurred Date to pull a bigger set of data and then filter it in my reporting spreadsheet?

Thanks,

Richard T