Variable names are changing case during runtime

First, some background.  Running Visual Studio Professional 2015.  This project has a mix of VB and C# code.  The code where the issue takes place is a VB controller.  This code has existed and functioned flawlessly for months until just last week.  

Code looks like:

<HttpGet()>

<Authorize(Roles:="role")>

Public Function BuildReport(param1 As Integer) As ActionResult

Try

Dim model = geGetModel(param1)

Dim result = New With {.success = True, .Model = model}

Return Json(result, JsonRequestBehavior.AllowGet)

End Try

End Function

Now the issue is that during runtime, when setting a breakpoint on the "Return Json..." line, inspection of the variable "result" reveals that "result" contains 2 properties - "success" and "model" with a lowercase "m".

Why are my variables changing case during runtime?