If you cancel your subscription within a paid period, you can read paid content until that period is over.
You have paid for the month of May. Your next billing date is on the 5th of June. You cancel your subscription on the 25th of May. You can continue to read premium content until the 4th of June.
Or how does it work? Does the access to paid content stop immediately when cancelling or does it keep going until the paid period is over? Perhaps @Kevin can clarify this to / for me?