* Add: Introduce a new REST API endpoint to create subscription(s) from a given order. This endpoint is available at POST `/wc/v3/orders/{order_id}/subscriptions` and accepts a single order ID.
* Add: When a customer toggles automatic renewals on or off via their My Account page, add a note to the subscription to record that event.
* Fix: Set and update a subscription's trial end date via the REST API.
* Fix: Ensure the `woocommerce_subscription_renewal_payment_complete` hook is always triggered when processing early renewals via the checkout page (introduced in 5.6.0).
* Fix: When a subscription is flagged as requiring manual payments, allow admin users to turn on automatic payments for a subscription via the Edit Subscription page by selecting a new payment method.
* Fix: When processing an early renewal order, make sure the suspension count is reset back to 0 on payment complete.
* Fix: Ensure proper backfilling of subscription metadata (i.e. dates and cache) to the postmeta table when HPOS is enabled and compatibility mode (data syncing) is turned on.
* Fix: Fetch and update the `_cancelled_email_sent` meta in a HPOS compatibile way.
* Dev: Introduce a new wcs_get_subscription_grouping_key() function to generate a unique key for a subscription based on its billing schedule. This function uses the existing recurring cart key concept.
* Dev: Deprecate the WC_Subscriptions_Synchroniser::add_to_recurring_cart_key(). Use WC_Subscriptions_Synchroniser::add_to_recurring_product_grouping_key() instead.
* Dev: Update subscriptions-core to 6.5.0
