diff --git a/classes.py b/classes.py
index 39dd7c3..4c72ce1 100644
--- a/classes.py
+++ b/classes.py
@@ -1087,6 +1087,8 @@ class Protocol():
                 self.irc.applyModes(channel, modes)
 
         our_ts = self.irc.channels[channel].ts
+        assert type(our_ts) == int, "Wrong type for our_ts (expected int, got %s)" % type(our_ts)
+        assert type(their_ts) == int, "Wrong type for our_ts (expected int, got %s)" % type(their_ts)
 
         if their_ts < our_ts:
             # Their TS is older than ours. We should clear our stored modes for the channel and
diff --git a/protocols/inspircd.py b/protocols/inspircd.py
index 2804f5a..1391baa 100644
--- a/protocols/inspircd.py
+++ b/protocols/inspircd.py
@@ -106,6 +106,8 @@ class InspIRCdProtocol(TS6BaseProtocol):
 
         # Strip out list-modes, they shouldn't ever be sent in FJOIN (protocol rules).
         modes = modes or self.irc.channels[channel].modes
+        orig_ts = self.irc.channels[channel].ts
+        ts = ts or orig_ts
 
         banmodes = []
         regularmodes = []
@@ -148,8 +150,6 @@ class InspIRCdProtocol(TS6BaseProtocol):
             self._send(server, "FMODE {channel} {ts} {modes} ".format(
                 ts=ts, channel=channel, modes=self.irc.joinModes(banmodes)))
 
-        orig_ts = self.irc.channels[channel].ts
-        ts = ts or orig_ts
         self.updateTS(channel, ts, changedmodes)
 
     def _operUp(self, target, opertype=None):
diff --git a/protocols/nefarious.py b/protocols/nefarious.py
index 8cb3d7e..cb7266d 100644
--- a/protocols/nefarious.py
+++ b/protocols/nefarious.py
@@ -475,6 +475,8 @@ class P10Protocol(Protocol):
         # <- AB B #test2 1460743539 +l 10 ABAAA:vo :%*!*@bad.host
         # <- AB B #test 1460747615 ABAAA:o :% ~ *!*@test.host
         modes = modes or self.irc.channels[channel].modes
+        orig_ts = self.irc.channels[channel].ts
+        ts = ts or orig_ts
 
         bans = []
         exempts = []
@@ -560,8 +562,6 @@ class P10Protocol(Protocol):
 
         self.irc.channels[channel].users.update(changedusers)
 
-        orig_ts = self.irc.channels[channel].ts
-        ts = ts or orig_ts
         self.updateTS(channel, ts, changedmodes)
 
     def spawnServer(self, name, sid=None, uplink=None, desc=None, endburst_delay=0):
diff --git a/protocols/ts6.py b/protocols/ts6.py
index daba1d4..0164334 100644
--- a/protocols/ts6.py
+++ b/protocols/ts6.py
@@ -101,6 +101,8 @@ class TS6Protocol(TS6BaseProtocol):
             raise LookupError('No such PyLink client exists.')
 
         modes = set(modes or self.irc.channels[channel].modes)
+        orig_ts = self.irc.channels[channel].ts
+        ts = ts or orig_ts
 
         # Get all the ban modes in a separate list. These are bursted using a separate BMASK
         # command.
@@ -151,8 +153,6 @@ class TS6Protocol(TS6BaseProtocol):
                 self._send(server, "BMASK {ts} {channel} {bmode} :{bans}".format(ts=ts,
                            channel=channel, bmode=bmode, bans=' '.join(bans)))
 
-        orig_ts = self.irc.channels[channel].ts
-        ts = ts or orig_ts
         self.updateTS(channel, ts, changedmodes)
 
     def mode(self, numeric, target, modes, ts=None):
diff --git a/protocols/unreal.py b/protocols/unreal.py
index 3417eb1..a78c4ec 100644
--- a/protocols/unreal.py
+++ b/protocols/unreal.py
@@ -148,6 +148,8 @@ class UnrealProtocol(TS6BaseProtocol):
             raise LookupError('No such PyLink server exists.')
 
         changedmodes = set(modes or self.irc.channels[channel].modes)
+        orig_ts = self.irc.channels[channel].ts
+        ts = ts or orig_ts
         uids = []
         namelist = []
 
@@ -184,8 +186,6 @@ class UnrealProtocol(TS6BaseProtocol):
 
         self.irc.channels[channel].users.update(uids)
 
-        orig_ts = self.irc.channels[channel].ts
-        ts = ts or orig_ts
         self.updateTS(channel, ts, changedmodes)
 
     def ping(self, source=None, target=None):