Update the duration and download page, the place where you can give a complimentary subscription or a paid subscription if you are using a different billing method.
The update allows you to schedule the renewal notifications if this subscription / membership is configured to get automated renewal notices.
You can enable the feature by adding a hidden or checkbox tag in the duration form, here are the two tags.
NOTE you can use only one tag in your form.
<input type="hidden" name="send_notifications" value="yes">
or
<input type="checkbox" name="send_notifications" value="yes">
I typically put it near the submit button.
<input type="submit" name="duration_submit" value="Submit">
If you need us to add the tag for you just let us know.