This webhook is sent each time an individual reward is successfully issued
to a user during a partner issuance job. If a batch contains 100 identifiers,
up to 100 individual reward.issued webhooks may be sent (one per
successful issuance).
The date the reward stops being redeemable (ISO8601), or null when the
campaign sets neither a redemption end date nor a relative window.When both are set, this is whichever comes first: the campaign’s
redeemable_to, or retire_after_days counted from the moment the reward
was issued. It is the same date the guest sees and the one redemption
enforces.
On an evergreen campaign — retire_after_days set and no redeemable_to —
expires_at is the only field in this payload carrying the reward’s expiry
date. campaign.redeemable_to is null by design.