Hello!
I have a subscription with grace period 14 days, if this subscription is expired and now on grace period i get this JSON:
[app1800_sub_personal_monthly] => Array
(
[billing_issues_detected_at] => 2021-08-27T08:29:54Z
[expires_date] => 2021-09-12T08:29:50Z
[grace_period_expires_date] => 2021-09-12T08:29:50Z
[is_sandbox] =>
[original_purchase_date] => 2021-07-27T08:29:52Z
[ownership_type] => PURCHASED
[period_type] => normal
[purchase_date] => 2021-07-27T08:29:50Z
[store] => app_store
[unsubscribe_detected_at] =>
)
Not so long ago, these fields were different and I use field “expires_date” to understand that the subscription expired and he now in the grace period