This has to do with the difference between the business date and activity date on a transaction that occurs around midnight, when the system might still be processing on today's business date but the clock has already moved past midnight to a different activity (system) date. For example, a member uses online banking after midnight on the 1st but we haven't yet done EOD for the 31st, then the last disbursed date on that loan account record will still be recorded as the 1st (the activity date).

Fortunately it's easy to work around this nuance by how you fill in the criteria on this report.

If you want to find data based on the last disbursed date and are using a previous month-end snapshot, to make sure you are getting the entire month always set the date range from the 1st of a month to the 1st​​​​​ of the next month​. 

For example, if you want all of January’s disbursements from the January EOM snapshot, you’d enter process date of January 20xx, then enter a date range of January 1 to February 1 in the Last disbursed date fields.  

This will make sure you catch any stray disbursements that happened at the very end of the day on the last day of January but, because of the timing of EOD around midnight, were actually booked with an activity date of the 1st.  

(TIP: Because you are using the month-end snapshot, which is captured during EOD at the end of the month, you won't have to worry about catching any other activity that occurred after BOD was run for the 1st if you use this technique. In other words, a transaction that happened at 8:00 in the morning on the 1st wouldn't be on that prior month's EOM snapshot anyway.)