diff --git a/plugins/relay.py b/plugins/relay.py
index 7b65f3f..5187571 100644
--- a/plugins/relay.py
+++ b/plugins/relay.py
@@ -479,9 +479,15 @@ def relayModes(irc, remoteirc, sender, channel, modes=None):
     log.debug('(%s) Relay mode: remotechan for %s on %s is %s', irc.name, channel, irc.name, remotechan)
     if remotechan is None:
         return
+    rc = remoteirc.channels[remotechan]
+    c = irc.channels[channel]
     if modes is None:
-        modes = irc.channels[channel].modes
-        log.debug('(%s) Relay mode: channel data for %s%s: %s', irc.name, remoteirc.name, remotechan, remoteirc.channels[remotechan])
+        modes = c.modes
+        log.debug('(%s) Relay mode: channel data for %s%s: %s', irc.name, remoteirc.name, remotechan, rc)
+    if c.ts > rc.ts:
+        log.debug('(%s) Relay mode: dropping relaying modes %r to %s%s, since our TS (%s) is greater than theirs (%s)',
+                  irc.name, modes, remoteirc.name, remotechan, c.ts, rc.ts)
+        return
     supported_modes = []
     log.debug('(%s) Relay mode: initial modelist for %s is %s', irc.name, channel, modes)
     for modepair in modes:
@@ -660,6 +666,8 @@ def relayJoins(irc, channel, users, ts, modes):
             # bother spawning it.
             continue
         log.debug('(%s) relayJoins: got %r for users', irc.name, users)
+        ts = irc.channels[channel].ts
+        rts = remoteirc.channels[remotechan].ts
         for user in users.copy():
             if utils.isInternalClient(irc, user) or user not in irc.users:
                 # We don't need to clone PyLink pseudoclients... That's
@@ -678,8 +686,10 @@ def relayJoins(irc, channel, users, ts, modes):
             # Only join users if they aren't already joined. This prevents op floods
             # on charybdis from all the SJOINing.
             if u not in remoteirc.channels[channel].users:
-                ts = irc.channels[channel].ts
-                prefixes = getPrefixModes(irc, remoteirc, channel, user)
+                if ts < rts:
+                    prefixes = getPrefixModes(irc, remoteirc, channel, user)
+                else:
+                    prefixes = ''
                 userpair = (prefixes, u)
                 queued_users.append(userpair)
                 log.debug('(%s) relayJoins: joining %s to %s%s', irc.name, userpair, remoteirc.name, remotechan)
diff --git a/protocols/inspircd.py b/protocols/inspircd.py
index 995dc6c..b88e9f5 100644
--- a/protocols/inspircd.py
+++ b/protocols/inspircd.py
@@ -367,6 +367,9 @@ def handle_fjoin(irc, servernumeric, command, args):
         log.debug('(%s) Setting channel TS of %s to %s from %s',
                   irc.name, channel, their_ts, our_ts)
         irc.channels[channel].ts = their_ts
+        irc.channels[channel].modes.clear()
+        for p in irc.channels[channel].prefixmodes.values():
+            p.clear()
     modestring = args[2:-1] or args[2]
     parsedmodes = utils.parseModes(irc, channel, modestring)
     utils.applyModes(irc, channel, parsedmodes)
diff --git a/protocols/ts6.py b/protocols/ts6.py
index 6a4f4e5..d4f617b 100644
--- a/protocols/ts6.py
+++ b/protocols/ts6.py
@@ -82,7 +82,6 @@ def sjoinServer(irc, server, channel, users, ts=None):
     log.debug("sending SJOIN to %s%s with ts %s (that's %r)", channel, irc.name, ts,
               time.strftime("%c", time.localtime(ts)))
     modes = [m for m in irc.channels[channel].modes if m[0] not in irc.cmodes['*A']]
-    changedmodes = []
     while users[:10]:
         uids = []
         namelist = []
@@ -107,7 +106,7 @@ def sjoinServer(irc, server, channel, users, ts=None):
                 ts=ts, users=namelist, channel=channel,
                 modes=utils.joinModes(modes)))
         irc.channels[channel].users.update(uids)
-    utils.applyModes(irc, channel, changedmodes)
+    utils.applyModes(irc, channel, modes)
 
 def _sendModes(irc, numeric, target, modes, ts=None):
     utils.applyModes(irc, target, modes)
@@ -372,6 +371,9 @@ def handle_sjoin(irc, servernumeric, command, args):
         log.debug('(%s) Setting channel TS of %s to %s from %s',
                   irc.name, channel, their_ts, our_ts)
         irc.channels[channel].ts = their_ts
+        irc.channels[channel].modes.clear()
+        for p in irc.channels[channel].prefixmodes.values():
+            p.clear()
     modestring = args[2:-1] or args[2]
     parsedmodes = utils.parseModes(irc, channel, modestring)
     utils.applyModes(irc, channel, parsedmodes)