The point that people here have is there's nothing stopping you paying for renewal on the day you want to use paid features such as open a ticket, or grab an update. You can delay renewal to the date you actually need it, in order to optimize your costs.
Imagine today you have a 2 hour shift today, and 1 espresso gives you 3 hours of wakefulness. You work from home and your shift starts at 10 am. You're ready at 9 am and drink your espresso and do nothing until 10 am. You work your shift until 12 pm and the espresso wears off.
You actually need to work overtime, an hour extra so now you need to drink a second espresso.
Now, if you had just waited until you really needed the espresso at the start of your shift, it would last you through the shift, and the unexpected overtime.
So the morale of the story is don't spend money until you really need to (don't have your espresso before you actually need it).