diff --git a/db/observers.go b/db/observers.go
index 36316db..fc10efa 100644
--- a/db/observers.go
+++ b/db/observers.go
@@ -321,10 +321,7 @@ func (s *Store) GetObserverActivity(ctx context.Context, observerID uuid.UUID, w
 		}
 		activity.PayloadTypes = make([]api.PayloadBreakdownItem, 0, len(typeRows))
 		for _, v := range typeRows {
-			payloadType := int16(-1)
-			if v.PayloadType != nil {
-				payloadType = *v.PayloadType
-			}
+			payloadType := v.PayloadType
 			activity.PayloadTypes = append(activity.PayloadTypes, api.PayloadBreakdownItem{
 				PayloadType:     payloadType,
 				PayloadTypeName: api.PayloadTypeName(payloadType),
diff --git a/db/sqlc/models.go b/db/sqlc/models.go
index 378fb60..47cce44 100644
--- a/db/sqlc/models.go
+++ b/db/sqlc/models.go
@@ -32,7 +32,7 @@ type AnalyticsLiveHourlyIataStat struct {
 
 type AnalyticsLiveObserverActivityHourly struct {
 	ObserverID   uuid.UUID          `json:"observer_id"`
-	PayloadType  *int16             `json:"payload_type"`
+	PayloadType  int16              `json:"payload_type"`
 	Bucket       pgtype.Timestamptz `json:"bucket"`
 	Observations int64              `json:"observations"`
 	AirtimeMs    float32            `json:"airtime_ms"`
@@ -244,7 +244,7 @@ type MvHourlyIataStat struct {
 
 type MvObserverActivityHourly struct {
 	ObserverID   uuid.UUID          `json:"observer_id"`
-	PayloadType  *int16             `json:"payload_type"`
+	PayloadType  int16              `json:"payload_type"`
 	Bucket       pgtype.Timestamptz `json:"bucket"`
 	Observations int64              `json:"observations"`
 	AirtimeMs    float32            `json:"airtime_ms"`
diff --git a/db/sqlc/queries.sql.go b/db/sqlc/queries.sql.go
index 489094c..054bc00 100644
--- a/db/sqlc/queries.sql.go
+++ b/db/sqlc/queries.sql.go
@@ -725,8 +725,8 @@ type GetObserverActivityHourlyPayloadTypesParams struct {
 }
 
 type GetObserverActivityHourlyPayloadTypesRow struct {
-	PayloadType *int16 `json:"payload_type"`
-	Count       int64  `json:"count"`
+	PayloadType int16 `json:"payload_type"`
+	Count       int64 `json:"count"`
 }
 
 func (q *Queries) GetObserverActivityHourlyPayloadTypes(ctx context.Context, arg GetObserverActivityHourlyPayloadTypesParams) ([]GetObserverActivityHourlyPayloadTypesRow, error) {
diff --git a/internal/api/handlers/observers.go b/internal/api/handlers/observers.go
index 15d52d6..66bddd8 100644
--- a/internal/api/handlers/observers.go
+++ b/internal/api/handlers/observers.go
@@ -256,7 +256,7 @@ var activityIntervals = map[string]time.Duration{
 //	@Param		observerId	path		string	true	"Observer UUID"
 //	@Param		range		query		string	false	"Trailing window as a Go duration, max 720h (default 24h); max 48h when interval is under 1h"
 //	@Param		interval	query		string	false	"Bucket size: 5m, 15m, 1h, 6h or 24h (default 15m)"
-//	@Param		until	query		int	false	"Optional exclusive end in epoch milliseconds; aligned down to a complete bucket, at most 30 days old"
+//	@Param		until	query		int	false	"Optional exclusive end in epoch milliseconds; aligned down to a complete bucket, at most 30 days old. Activity uses this window; summary freshness/latestRecordedAt and the last complete hour are measured at response generation time, independently of until."
 //	@Success	200			{object}	api.ObserverActivity
 //	@Failure	400			{object}	handlers.APIError
 //	@Failure	404			{object}	handlers.APIError
diff --git a/sqlc.yaml b/sqlc.yaml
index b5e86b8..9210892 100644
--- a/sqlc.yaml
+++ b/sqlc.yaml
@@ -31,5 +31,3 @@ sql:
           - column: "mv_top_advertisers_by_iata.name"
             go_type: {type: "string", pointer: true}
 
-          - column: "mv_observer_activity_hourly.payload_type"
-            go_type: {type: "int16", pointer: true}