- create a new task, temporary, to load the history. Set it the task as full load only, and of course that it does not drop the target if it exists. In the task you can put a filter condition, on a date field. I did not test it but I think something similar to
$MY_DATE_FIELD <= date('now','start of month')
so that it will only load data from the past and will not interfere with the real time capture.