My bad: There is a Windows version and another for OS X
As to salesmen ... they haven't a clue. There are many Hughes system platforms and plan variations in use. In some of the legacy plans with daily allowance refills, there was a "rollover" for up to two days worth of data but that never has been a part of any Gen4 plan.
If salesmen have a function beyond taking up space, I'm baffled as to what it is.
If you are searching for when a past loss occurred you seem to be left with this:
Select your Modem type
Enter your SAN (remember to capitalize the letters DSSxxxxxx)
Select a date.
That will provide hourly usage details for a given 24hr period. You could then take screenshots and assemble them into some kind of timeline.
I seem to recall you being located in the pacific time zone, so as noted in a previous post the hourly details posted above are listed in eastern so a "correction" needs to be applied.