v2 server notifications meaning (renewal & grace)

I received the following notifications (in this order) for the subscription:

date, type, subtype
2023-10-09 10:49:17,SUBSCRIBED,INITIAL_BUY
2023-10-16 03:46:44,DID_CHANGE_RENEWAL_STATUS,AUTO_RENEW_DISABLED
2023-10-16 10:49:19,DID_FAIL_TO_RENEW,GRACE_PERIOD
2023-10-16 13:14:36,EXPIRED,BILLING_RETRY

What do these mean? Why is there a DID_FAIL_TO_RENEW GRACE_PERIOD notification when the user already disabled auto-renew? Why did it expire in 2.5 hours? Why isn't there a GRACE_PERIOD_EXPIRED notification?"

Subscriptions do not renew exactly on the expiration time. In this case, the user subscribed, then we attempted to renew sending the user into grace, they then disabled renewal, and then we expired their subscription. There was no GRACE_PERIOD_EXPIRED because after deactivating auto renewal they went straight to the EXPIRED state.

v2 server notifications meaning (renewal & grace)
 
 
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