The "Use latest lot numbers" doesn't work after receiving data from external lab
The "Use latest lot numbers" functionality finds the latest RNA item and pick lote number from that one. Now that we are receiving data from an external lab, the latest RNA may be one that was processed there. We don't receive any lot number information from the external lab. In any case, the lot numbers we use here are most likely different, so we should completely ignore external samples in this function.