diff --git a/CHANGELOG.md b/CHANGELOG.md
index d3a8ebe2..2481f228 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -54,9 +54,13 @@ are the full record until the next release.
 
 - **The fire_scheduled_purchases sweep is now on by default on every
   Terraform platform** (Lambda, Fargate, Cloud Run, GKE, Container Apps and
-  AKS), every 15 minutes. It executes delayed auto-approved purchases once
-  their scheduled time passes; until now they never ran unless the operator
-  turned the sweep on. The server refuses (and sends the purchase-failed
+  AKS), every 15 minutes. It carries out every purchase a person approves
+  while a purchase delay is set (`purchase_delay_hours` > 0; the migrated
+  default is 0, which executes approvals immediately) once the delay ends;
+  until now those approvals never executed unless the operator turned the
+  sweep on. Keep it on unless `purchase_delay_hours` stays 0. GKE deployed from `terraform/environments/gcp` still gets no Cloud
+  Scheduler jobs, this one included (that environment doesn't pass
+  `enable_scheduled_tasks` to GKE). The server refuses (and sends the purchase-failed
   alert for) any purchase due more than 24h ago, so the first run cannot buy
   a stale backlog. Set `enable_fire_scheduled_purchases_schedule = false` to
   opt out. The process_scheduled_purchases sweep stays opt-in (#712)
diff --git a/terraform/environments/aws/variables.tf b/terraform/environments/aws/variables.tf
index b16ded68..ed893f19 100644
--- a/terraform/environments/aws/variables.tf
+++ b/terraform/environments/aws/variables.tf
@@ -395,7 +395,7 @@ variable "ladder_run_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/environments/azure/variables.tf b/terraform/environments/azure/variables.tf
index 477f9f3d..6f729e7e 100644
--- a/terraform/environments/azure/variables.tf
+++ b/terraform/environments/azure/variables.tf
@@ -444,7 +444,7 @@ variable "analytics_collect_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/environments/gcp/variables.tf b/terraform/environments/gcp/variables.tf
index 06034bbb..8b24101f 100644
--- a/terraform/environments/gcp/variables.tf
+++ b/terraform/environments/gcp/variables.tf
@@ -370,7 +370,7 @@ variable "analytics_collect_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/modules/compute/aws/fargate/variables.tf b/terraform/modules/compute/aws/fargate/variables.tf
index 55744b93..dcb4cd9c 100644
--- a/terraform/modules/compute/aws/fargate/variables.tf
+++ b/terraform/modules/compute/aws/fargate/variables.tf
@@ -226,7 +226,7 @@ variable "ladder_run_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/modules/compute/aws/lambda/main.tf b/terraform/modules/compute/aws/lambda/main.tf
index 91968553..14d0ea71 100644
--- a/terraform/modules/compute/aws/lambda/main.tf
+++ b/terraform/modules/compute/aws/lambda/main.tf
@@ -775,9 +775,9 @@ resource "aws_lambda_permission" "eventbridge_ladder_run" {
 # Frequent tick that invokes the fire_scheduled_purchases task:
 # scans purchase_executions in status=scheduled whose
 # scheduled_execution_at is in the past and fires each one. This
-# sweep is the runtime mechanism that makes auto-approve delayed
-# purchases actually execute; without it, scheduled tranches would
-# never fire between daily ladder runs. On by default (owner decision
+# sweep is what carries out a purchase a person approved while a
+# purchase delay is set (purchase_delay_hours > 0); without it those
+# approvals never execute. On by default (owner decision
 # for #712): the server refuses any row due more than 24h ago (#1549),
 # so a first tick after enabling cannot buy a stale backlog.
 
diff --git a/terraform/modules/compute/aws/lambda/variables.tf b/terraform/modules/compute/aws/lambda/variables.tf
index 770799b3..3d928f84 100644
--- a/terraform/modules/compute/aws/lambda/variables.tf
+++ b/terraform/modules/compute/aws/lambda/variables.tf
@@ -246,7 +246,7 @@ variable "ladder_run_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/modules/compute/azure/aks/variables.tf b/terraform/modules/compute/azure/aks/variables.tf
index c29cafd2..19494d33 100644
--- a/terraform/modules/compute/azure/aks/variables.tf
+++ b/terraform/modules/compute/azure/aks/variables.tf
@@ -277,7 +277,7 @@ variable "analytics_collect_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/modules/compute/azure/container-apps/variables.tf b/terraform/modules/compute/azure/container-apps/variables.tf
index c16bc6dc..8953d4e4 100644
--- a/terraform/modules/compute/azure/container-apps/variables.tf
+++ b/terraform/modules/compute/azure/container-apps/variables.tf
@@ -285,7 +285,7 @@ variable "analytics_collect_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/modules/compute/gcp/cloud-run/variables.tf b/terraform/modules/compute/gcp/cloud-run/variables.tf
index defe6199..b3bcb71d 100644
--- a/terraform/modules/compute/gcp/cloud-run/variables.tf
+++ b/terraform/modules/compute/gcp/cloud-run/variables.tf
@@ -216,7 +216,7 @@ variable "analytics_collect_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }
diff --git a/terraform/modules/compute/gcp/gke/variables.tf b/terraform/modules/compute/gcp/gke/variables.tf
index 0d1cea34..01a9766a 100644
--- a/terraform/modules/compute/gcp/gke/variables.tf
+++ b/terraform/modules/compute/gcp/gke/variables.tf
@@ -306,7 +306,7 @@ variable "analytics_collect_schedule" {
 }
 
 variable "enable_fire_scheduled_purchases_schedule" {
-  description = "Schedule the fire_scheduled_purchases sweep, which executes delayed auto-approved purchases once their scheduled time has passed. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
+  description = "Schedule the fire_scheduled_purchases sweep, which carries out every purchase a person approves while a purchase delay is set (purchase_delay_hours > 0; the migrated default is 0, which executes approvals immediately) once the delay ends. With the sweep off, those approved purchases stay scheduled and never execute, with no alert, so turn it off only where purchase_delay_hours stays 0. On by default: the server refuses, and alerts on, any purchase due more than 24h ago (SCHEDULED_PURCHASE_MAX_OVERDUE, #1549), so turning it on cannot buy a stale backlog. Set false to opt out."
   type        = bool
   default     = true
 }