When generating statements up to a particular date (e.g end of last month) MYOB provides a useful tickbox option - "Only included statements up to invoice date". However, you don't honour the "Includ...
I agree this is a nightmare. Every month we have cusotmers complain to us about getting blank statements. We tick all the right boxes however forward invoices receive blank statements. We have had cusotmers get really mad because they think we are asking them to pay in advance which we don't do. Come on MYOB do better and fix this problem. It can't be that hard.