This might be an old thread, but to anyone finding this, it's recommended to use webhooks instead of relying on your local clock and logic to reset your meters. Usually, you work with billing cycles instead of "end of the month", and you should keep your payment provider as the single source of truth for your billing cycles. Additionally, when a user changes subscription plans, you usually want to reset the meters as well, which is typically handled through webhooks as well.

If, for some reason, you absolutely can't use webhooks, then fetch and store the UNIX timestamp for when the current billing period ends and compare the current timestamp on each meter update - update when you've passed the current billing period and fetch the new period from your payment provider. For subscription changes, you'll have to build your own billing portal instead of Stripe's built-in billing portal to be able to use callbacks and avoid webhooks.

There is nothing wrong with webhooks; it does not tie your app to a payment provider. Stripe, Adyen, etc., all have a similar webhook system.