We need to leave a window with the Declined on, but then after 12 months, reintroduce them as upgradable.

We don't currently have an expiration period baked in. Since the donors are giving every month, that new donation will trigger a recalculation of the eligibility, so it should be enough to just modify the condition around having those activities.

'Recurring Upgrade Declined' is an activity type in CiviCRM. We don't export the full activity history to Acoustic - instead, in the nightly export, we calculate eligibility for upgrade for each donor that's been touched in the last 2 weeks, and just export a single yes/no field to Acoustic.