The only thing I can suggest at the moment is either:
- turn off automatic reminders and manually send them (as per @Glenn’s post here), or
- disable the invoice reminders for individual invoices (see below)
To disable individual invoice reminders, go to Sales >> Outstanding Invoices (or click the ‘Money owed to you’ box on the dashboard), and then click the timer next to the invoice you wish to amend the reminders for:
Then just tick/amend the boxes that you wish:
You may also wish to add your vote to the topic I linked to above.