diff --git a/back/methods/collection/assignCollection.js b/back/methods/collection/assignCollection.js
index 2ff37ab59..2a7ec9ad5 100644
--- a/back/methods/collection/assignCollection.js
+++ b/back/methods/collection/assignCollection.js
@@ -19,8 +19,15 @@ module.exports = Self => {
 
         if (typeof options == 'object')
             Object.assign(myOptions, options);
-        const [info, info2, [{'@vCollectionFk': collectionFk}]] = await Self.rawSql(
-            'CALL vn.collection_getAssigned(?, @vCollectionFk);SELECT @vCollectionFk', [userId], myOptions);
+
+        const randStr = Math.random().toString(36).substring(3);
+        const result = await Self.rawSql(`
+            CALL vn.collection_getAssigned(?, @vCollectionFk);
+            SELECT @vCollectionFk ?
+            `, [userId, randStr], myOptions);
+
+        const collectionFk = result.find(item => item[0]?.[randStr] !== undefined)?.[0]?.[randStr];
+
         if (!collectionFk) throw new UserError('There are not picking tickets');
         await Self.rawSql('CALL vn.collection_printSticker(?, NULL)', [collectionFk], myOptions);
 
diff --git a/db/routines/vn/procedures/collection_getAssigned.sql b/db/routines/vn/procedures/collection_getAssigned.sql
index 518e2dd7b..7151129bf 100644
--- a/db/routines/vn/procedures/collection_getAssigned.sql
+++ b/db/routines/vn/procedures/collection_getAssigned.sql
@@ -5,100 +5,139 @@ CREATE OR REPLACE DEFINER=`vn`@`localhost` PROCEDURE `vn`.`collection_getAssigne
 )
 BEGIN
 /**
- * Comprueba si existen colecciones libres que se ajustan al perfil del usuario
- * y le asigna la más antigua.
- * Añade un registro al semillero de colecciones y hace la reserva para la colección
- * 
+ * Comprueba si existen colecciones libres que se ajustan
+ * al perfil del usuario y le asigna la más antigua.
+ * Añade un registro al semillero de colecciones.
+ *
  * @param vUserFk Id de usuario
  * @param vCollectionFk Id de colección
  */
 	DECLARE vHasTooMuchCollections BOOL;
-	DECLARE vItemPackingTypeFk VARCHAR(1);
-	DECLARE vWarehouseFk INT;
-	DECLARE vLockName VARCHAR(215);
-	DECLARE vLockTime INT DEFAULT 30;
+	DECLARE vDone BOOL DEFAULT FALSE;
+	DECLARE vCollectionWorker INT;
+	DECLARE vMaxNotAssignedCollectionLifeTime TIME;
+
+	DECLARE vCollections CURSOR FOR
+		WITH collections AS (			
+			SELECT tc.collectionFk, 
+					SUM(sv.volume) volume,
+					c.saleTotalCount,
+					c.itemPackingTypeFk,
+					c.trainFk,
+					c.warehouseFk,
+					c.wagons
+				FROM vn.ticketCollection tc
+					JOIN vn.collection c ON c.id = tc.collectionFk 
+					JOIN vn.saleVolume sv ON sv.ticketFk = tc.ticketFk
+				WHERE c.workerFk IS NULL 
+					AND sv.shipped >= util.VN_CURDATE()
+				GROUP BY tc.collectionFk
+		) SELECT c.collectionFk
+			FROM collections c
+				JOIN vn.operator o
+			WHERE o.workerFk = vUserFk
+				AND (c.saleTotalCount <= o.linesLimit OR o.linesLimit IS NULL)
+				AND (c.itemPackingTypeFk = o.itemPackingTypeFk OR o.itemPackingTypeFk IS NULL)
+				AND o.numberOfWagons = c.wagons
+				AND o.trainFk = c.trainFk
+				AND o.warehouseFk = c.warehouseFk;
+
+	DECLARE CONTINUE HANDLER FOR NOT FOUND SET vDone = TRUE;
+	-- Si hay colecciones sin terminar, sale del proceso
 
 	DECLARE EXIT HANDLER FOR SQLEXCEPTION
 	BEGIN
-		IF vLockName IS NOT NULL THEN
-			DO RELEASE_LOCK(vLockName);
-		END IF;
-		
+		ROLLBACK;
 		RESIGNAL;
 	END;
 
-	-- Si hay colecciones sin terminar, sale del proceso
 	CALL collection_get(vUserFk);
 
-	SELECT (pc.maxNotReadyCollections - COUNT(*)) <= 0,
-			pc.collection_assign_lockname
-		INTO vHasTooMuchCollections,
-			vLockName
-		FROM tmp.collection c
-			JOIN productionConfig pc;
+	SELECT (pc.maxNotReadyCollections - COUNT(*)) <= 0, pc.maxNotAssignedCollectionLifeTime 
+			INTO vHasTooMuchCollections, vMaxNotAssignedCollectionLifeTime
+		FROM productionConfig pc
+			LEFT JOIN tmp.collection ON TRUE;
 
 	DROP TEMPORARY TABLE tmp.collection;
 
 	IF vHasTooMuchCollections THEN
-		CALL util.throw('There are pending collections');
-	END IF;
-
-	SELECT warehouseFk, itemPackingTypeFk
-		INTO vWarehouseFk, vItemPackingTypeFk
-		FROM operator
-		WHERE workerFk = vUserFk;
-
-	SET vLockName = CONCAT_WS('/',
-		vLockName,
-		vWarehouseFk,
-		vItemPackingTypeFk
-	);
-
-	IF NOT GET_LOCK(vLockName, vLockTime) THEN
-		CALL util.throw(CONCAT('Cannot get lock: ', vLockName));
+		CALL util.throw('Hay colecciones pendientes');
 	END IF;
 
 	-- Se eliminan las colecciones sin asignar que estan obsoletas
-	INSERT INTO ticketTracking(stateFk, ticketFk)
-			SELECT s.id, tc.ticketFk
-				FROM collection c
-					JOIN ticketCollection tc ON tc.collectionFk = c.id
-					JOIN state s ON s.code = 'PRINTED_AUTO'
-					JOIN productionConfig pc 
-			WHERE c.workerFk IS NULL 
-				AND TIMEDIFF(util.VN_NOW(), c.created) > pc.maxNotAssignedCollectionLifeTime;
 
-	DELETE c
-		FROM collection c
-			JOIN productionConfig pc 
-		WHERE c.workerFk IS NULL 
-			AND TIMEDIFF(util.VN_NOW(), c.created) > pc.maxNotAssignedCollectionLifeTime;
+	INSERT INTO ticketTracking(stateFk, ticketFk)
+		SELECT s.id, tc.ticketFk
+			FROM `collection` c
+				JOIN ticketCollection tc ON tc.collectionFk = c.id
+				JOIN `state` s ON s.code = 'PRINTED_AUTO'
+			WHERE c.workerFk IS NULL 
+				AND TIMEDIFF(util.VN_NOW(), c.created) > vMaxNotAssignedCollectionLifeTime;
+
+	DELETE FROM `collection` 
+		WHERE workerFk IS NULL 
+			AND TIMEDIFF(util.VN_NOW(), created) > vMaxNotAssignedCollectionLifeTime;
 
 	-- Se añade registro al semillero
-	INSERT INTO collectionHotbed
-		SET userFk = vUserFk;
+
+	INSERT INTO collectionHotbed(userFk) VALUES(vUserFk);
 
 	-- Comprueba si hay colecciones disponibles que se ajustan a su configuracion
-	SELECT MIN(c.id) INTO vCollectionFk
-		FROM collection c 
-			JOIN operator o ON (o.itemPackingTypeFk = c.itemPackingTypeFk 
-					OR c.itemPackingTypeFk IS NULL)
-				AND o.numberOfWagons = c.wagons
-				AND o.trainFk = c.trainFk
-				AND o.warehouseFk = c.warehouseFk
-				AND c.workerFk IS NULL
-		WHERE o.workerFk = vUserFk;
+
+	OPEN vCollections;
+	l: LOOP
+		SET vDone = FALSE;
+		FETCH vCollections INTO vCollectionFk;
+
+		IF vDone THEN
+			LEAVE l;
+		END IF;
+
+		BEGIN
+			DECLARE EXIT HANDLER FOR SQLEXCEPTION
+			BEGIN
+				ROLLBACK;
+				SET vCollectionFk = NULL;
+				RESIGNAL;
+			END;
+
+			START TRANSACTION;
+
+			SELECT workerFk INTO vCollectionWorker
+				FROM `collection` 
+				WHERE id = vCollectionFk FOR UPDATE;
+
+			IF vCollectionWorker IS NULL THEN
+				UPDATE `collection`
+					SET workerFk = vUserFk
+					WHERE id = vCollectionFk;
+
+				COMMIT;
+				LEAVE l;
+			END IF;
+
+			ROLLBACK;
+		END;
+	END LOOP;
+	CLOSE vCollections;
 
 	IF vCollectionFk IS NULL THEN
 		CALL collection_new(vUserFk, vCollectionFk);
+		
+		START TRANSACTION;
+
+		SELECT workerFk INTO vCollectionWorker
+			FROM `collection` 
+			WHERE id = vCollectionFk FOR UPDATE;
+
+		IF vCollectionWorker IS NULL THEN
+			UPDATE `collection`
+				SET workerFk = vUserFk
+				WHERE id = vCollectionFk;
+		END IF;
+
+		COMMIT;
 	END IF;
-
-	UPDATE collection
-		SET workerFk = vUserFk
-		WHERE id = vCollectionFk;
-
 	CALL itemShelvingSale_addByCollection(vCollectionFk);
-	
-	DO RELEASE_LOCK(vLockName);
 END$$
 DELIMITER ;
\ No newline at end of file
diff --git a/db/versions/11289-azureAralia/00-firstScript.sql b/db/versions/11289-azureAralia/00-firstScript.sql
new file mode 100644
index 000000000..ab091f53f
--- /dev/null
+++ b/db/versions/11289-azureAralia/00-firstScript.sql
@@ -0,0 +1,2 @@
+
+ALTER TABLE vn.sector ADD isOnReservationMode tinyint(1) DEFAULT FALSE NULL;
diff --git a/modules/shelving/back/models/sector.json b/modules/shelving/back/models/sector.json
index 61d8d0628..16aa0ba6a 100644
--- a/modules/shelving/back/models/sector.json
+++ b/modules/shelving/back/models/sector.json
@@ -59,6 +59,9 @@
         "isReserve": {
             "type": "boolean",
             "required": true
+        },
+        "isOnReservationMode": {
+            "type": "boolean"
         }
     }
-}
+}
\ No newline at end of file
diff --git a/modules/worker/back/methods/device/handle-user.js b/modules/worker/back/methods/device/handle-user.js
index 55302c1cb..abafffd55 100644
--- a/modules/worker/back/methods/device/handle-user.js
+++ b/modules/worker/back/methods/device/handle-user.js
@@ -87,7 +87,7 @@ module.exports = Self => {
                 {
                     relation: 'sector',
                     scope: {
-                        fields: ['warehouseFk', 'description'],
+                        fields: ['warehouseFk', 'description', 'isOnReservationMode'],
                     }
                 }, {
                     relation: 'printer',