Subscription amount cannot be updated for a future date using REST API

I am trying to programmatically update the recurring subscription amount using Subscription Update API – https://woocommerce.github.io/subscriptions-rest-api-docs/#update-a-subscription

When we update a subscription, it must be applicable from next renewal date. However, the subscription amount is changed with immediate effect instead of next renewal date.

Let me know what am I missing. Thanks in advance.

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