diff --git a/r2/r2/lib/promote.py b/r2/r2/lib/promote.py
index ae7312168..7f7121a51 100644
--- a/r2/r2/lib/promote.py
+++ b/r2/r2/lib/promote.py
@@ -692,7 +692,7 @@ def get_live_promotions(srids, from_permacache=True):
     return links, weights
 
 
-def set_live_promotions(links, weights, which=("permacache",)):
+def set_live_promotions(links, weights, which=("cass", "permacache")):
     if "permacache" in which:
         timer = g.stats.get_timer("promote.set_live.permacache")
         timer.start()
@@ -997,8 +997,8 @@ def run_changed(drain=False, limit=100, sleep_time=10, verbose=True):
         if QUEUE_ALL in items:
             # QUEUE_ALL is just an indicator to run make_daily_promotions.
             # There's no promotion log to update in this case.
-            print "Received QUEUE_ALL message"
-            items.remove(QUEUE_ALL)
+            print "Received %s QUEUE_ALL message(s)" % items.count(QUEUE_ALL)
+            items = [i for i in items if i != QUEUE_ALL]
         make_daily_promotions()
         links = Link._by_fullname([i["link"] for i in items])
         for item in items:
diff --git a/r2/r2/models/bidding.py b/r2/r2/models/bidding.py
index ad8462ec6..0720eae26 100644
--- a/r2/r2/models/bidding.py
+++ b/r2/r2/models/bidding.py
@@ -36,14 +36,14 @@ from sqlalchemy.orm.exc import NoResultFound
 from sqlalchemy.dialects.postgresql.base import PGInet as Inet
 from sqlalchemy.ext.declarative import declarative_base
 
-import r2.lib.db.operators as db_ops
+from r2.lib.utils import Enum
+from r2.models.account import Account
+from r2.models import Link, Subreddit
 from r2.lib.db.thing import Thing, NotFound
 import r2.lib.db.tdb_cassandra as tdb_cassandra
 from r2.lib.memoize import memoize
 
 from r2.lib.utils import Enum, fetch_things2, to_date
-from r2.models.account import Account
-from r2.models import Link, Subreddit
 
 
 engine = g.dbm.get_engine('authorize')
@@ -528,10 +528,14 @@ class SponsorBoxWeightings(object):
         def _id(self):
             return int(self)
     
-    def __init__(self, subreddit, timestamp, items, is_srid=True):
+    def __init__(self, subreddit, timestamp, items, is_srid=True,
+                 mutator=None):
         self.subreddit = self.ID(subreddit) if is_srid else subreddit
         self.items = items
         self.timeslot = tdb_cassandra.date_serializer.pack(timestamp)
+        # If a Mutator is not passed in, the ColumnFamily has a compatible
+        # insert() method
+        self.mutator = mutator or self._cf
     
     @classmethod
     def index_rowkey(cls, subreddit):
@@ -576,15 +580,15 @@ class SponsorBoxWeightings(object):
     @tdb_cassandra.will_write
     def _set_as_latest(self):
         rowkey = self.rowkey() if not self.empty else ''
-        self._cf.insert(self.index_rowkey(self.subreddit),
-                        {self._IDX_COLUMN_KEY: rowkey},
-                        ttl=self._ttl)
+        self.mutator.insert(self.index_rowkey(self.subreddit),
+                            {self._IDX_COLUMN_KEY: rowkey},
+                            ttl=self._ttl)
     
     @tdb_cassandra.will_write
     def set_timeslots(self):
         campaign_weights = self._calculate_weights()
         if campaign_weights:
-            self._cf.insert(self.rowkey(), campaign_weights, ttl=self._ttl)
+            self.mutator.insert(self.rowkey(), campaign_weights, ttl=self._ttl)
     
     def _calculate_weights(self):
         # Distribute the ads as "slices" of the range 0 - 2^32
@@ -613,36 +617,36 @@ class SponsorBoxWeightings(object):
         if '' in weights:
             weights[cls.FRONT_PAGE] = weights.pop('')
         
-        timeslot = datetime.datetime.now(g.tz)
+        today = datetime.datetime.now(g.tz)
         
         while weights:
             srid, promos = weights.popitem()
             weight_refs = [WeightingRef.from_promo(*promo) for promo in promos]
-            sbw = cls(srid, timeslot, weight_refs, is_srid=True)
+            sbw = cls(srid, today, weight_refs, is_srid=True)
             sbw.set_as_latest()
         
         # Clear out expired ads
-        query = Subreddit._query(sort=db_ops.desc('_date'), data=False)
-        for subreddit in fetch_things2(query):
-            if subreddit._id not in all_weights:
-                cls.clear(subreddit, timeslot=timeslot)
+        
+        # First, figure out which subreddits may have had ads
+        yesterday = today - datetime.timedelta(days=1)
+        tomorrow = today + datetime.timedelta(days=1)
+        promo_weights = PromotionWeights.get_campaigns(yesterday, tomorrow)
+        subreddit_names = set(p.sr_name for p in promo_weights)
+        subreddits = Subreddit._by_name(subreddit_names).values()
+        
+        # Next, clear out any ads from those subreddits, if and only if
+        # that subreddit wasn't updated already during this function call
+        mutator = cls._cf.batch()
+        for sr in subreddits:
+            if sr._id not in all_weights:
+                cls.clear(sr, timeslot=today, mutator=mutator)
+        mutator.send()
     
     @classmethod
-    def clear(cls, srid, timeslot=None, is_srid=False):
+    def clear(cls, srid, timeslot=None, is_srid=False, mutator=None):
         timeslot = timeslot or datetime.datetime.now(g.tz)
-        cls(srid, timeslot, [], is_srid=is_srid).set_as_latest()
-    
-    @classmethod
-    def remove_link(cls, link_fn, from_subreddits, include_all_sr=True):
-        now = datetime.datetime.now(g.tz)
-        if include_all_sr:
-            srs = itertools.chain(from_subreddits, [cls.ID(cls.ALL_ADS_ID)])
-        else:
-            srs = from_subreddits
-        for subreddit in srs:
-            current = cls.load_by_sr(subreddit._id)
-            updated = [r for r in current if r.data['link'] != link_fn]
-            cls(subreddit, now, updated).set_as_latest()
+        sbw = cls(srid, timeslot, [], is_srid=is_srid, mutator=mutator)
+        sbw.set_as_latest()
 
 
 # do all the leg work of creating/connecting to tables