As more and more business models favor subscriptions, AppleCare+ is no exception. Previously, apple customers would pay upfront when they bought their device for a set service term of AppleCare+. The paid extended warranty program from Apple extends the time for which you can get free and discounted repairs on your Apple device as well as the phone/chat support.
Previously, you’d pay a one-time fee for a set two-year term of warranty. Now, in addition to that, you have the option to pay a monthly subscription fee which, even though it ends up being more expensive per month than the prepaid, your device will be covered by AppleCare+ until canceled. The prepaid option can’t be renewed.
The new subscription option is great if you plan to keep insurance on your Apple device for more than the 2-year prepaid option. It’s great that for the time being, Apple still allows you to buy a set term without renewal, so they’re not removing any functionality.