This filters how many days before expiration PMPro should send expiration warning emails. The default is 7 days.
Here is how the filter looks in the code:
apply_filters( 'pmpro_email_days_before_expiration', 7 );
If you’d like to send more than 1 expiration warning email or customize this interval, use the Extra Expiration Warning Emails Add On.
Here is a gist showing how to use this filter.
- integer; a number representing the days before expiration to send the notice