diff --git a/tests/ms/MsTest.cpp b/tests/ms/MsTest.cpp
index 0895e4d..01f2642 100644
--- a/tests/ms/MsTest.cpp
+++ b/tests/ms/MsTest.cpp
@@ -232,6 +232,99 @@
 	printf("=== end %s ===\n", __func__);
 }
 
+static void test_ms_change_tlli()
+{
+	uint32_t start_tlli = 0xaa000000;
+	uint32_t new_ms_tlli = 0xff001111;
+	uint32_t other_sgsn_tlli = 0xff00eeee;
+	GprsMs *ms;
+
+	printf("=== start %s ===\n", __func__);
+
+	ms = new GprsMs(start_tlli);
+
+	OSMO_ASSERT(ms->is_idle());
+
+	/* MS announces TLLI, SGSN uses it immediately */
+	ms->set_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(start_tlli));
+
+	ms->confirm_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(!ms->check_tlli(start_tlli));
+
+	/* MS announces TLLI, SGSN uses it later */
+	ms->set_tlli(start_tlli);
+	ms->confirm_tlli(start_tlli);
+
+	ms->set_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(start_tlli));
+
+	ms->confirm_tlli(start_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(start_tlli));
+
+	ms->set_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(start_tlli));
+
+	ms->confirm_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(!ms->check_tlli(start_tlli));
+
+	/* MS announces TLLI, SGSN uses it later after another new TLLI */
+	ms->set_tlli(start_tlli);
+	ms->confirm_tlli(start_tlli);
+
+	ms->set_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(start_tlli));
+
+	ms->confirm_tlli(other_sgsn_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(other_sgsn_tlli));
+
+	ms->set_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(other_sgsn_tlli));
+
+	ms->confirm_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(!ms->check_tlli(start_tlli));
+	OSMO_ASSERT(!ms->check_tlli(other_sgsn_tlli));
+
+	/* SGSN uses the new TLLI before it is announced by the MS (shouldn't
+	 * happen in normal use) */
+	ms->set_tlli(start_tlli);
+	ms->confirm_tlli(start_tlli);
+
+	ms->confirm_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == start_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(ms->check_tlli(start_tlli));
+
+	ms->set_tlli(new_ms_tlli);
+	OSMO_ASSERT(ms->tlli() == new_ms_tlli);
+	OSMO_ASSERT(ms->check_tlli(new_ms_tlli));
+	OSMO_ASSERT(!ms->check_tlli(start_tlli));
+
+	delete ms;
+
+	printf("=== end %s ===\n", __func__);
+}
+
 static void test_ms_storage()
 {
 	uint32_t tlli = 0xffeeddbb;
@@ -320,6 +413,7 @@
 	test_ms_state();
 	test_ms_callback();
 	test_ms_replace_tbf();
+	test_ms_change_tlli();
 	test_ms_storage();
 
 	if (getenv("TALLOC_REPORT_FULL"))
diff --git a/tests/ms/MsTest.err b/tests/ms/MsTest.err
index 091e0c8..bec98b9 100644
--- a/tests/ms/MsTest.err
+++ b/tests/ms/MsTest.err
@@ -18,6 +18,23 @@
 Detaching TBF from MS object, TLLI = 0xffeeddbb, TBF = TBF(TFI=0 TLLI=0x00000000 DIR=UL STATE=NULL)
 Detaching TBF from MS object, TLLI = 0xffeeddbb, TBF = TBF(TFI=0 TLLI=0x00000000 DIR=DL STATE=NULL)
 Destroying MS object, TLLI = 0xffeeddbb
+Creating MS object, TLLI = 0xaa000000
+Modifying MS object, UL TLLI: 0xaa000000 -> 0xff001111, not yet confirmed
+Modifying MS object, TLLI: 0xff001111 confirmed
+Modifying MS object, UL TLLI: 0xff001111 -> 0xaa000000, not yet confirmed
+Modifying MS object, TLLI: 0xaa000000 confirmed
+Modifying MS object, UL TLLI: 0xaa000000 -> 0xff001111, not yet confirmed
+Modifying MS object, TLLI: 0xff001111 confirmed
+Modifying MS object, UL TLLI: 0xff001111 -> 0xaa000000, not yet confirmed
+Modifying MS object, TLLI: 0xaa000000 confirmed
+Modifying MS object, UL TLLI: 0xaa000000 -> 0xff001111, not yet confirmed
+The MS object cannot fully confirm an unexpected TLLI: 0xff00eeee, partly confirmed
+Modifying MS object, TLLI: 0xff001111 confirmed
+Modifying MS object, UL TLLI: 0xff001111 -> 0xaa000000, not yet confirmed
+Modifying MS object, TLLI: 0xaa000000 confirmed
+The MS object cannot fully confirm an unexpected TLLI: 0xff001111, partly confirmed
+Modifying MS object, TLLI: 0xaa000000 -> 0xff001111, already confirmed partly
+Destroying MS object, TLLI = 0xff001111
 Creating MS object, TLLI = 0xffeeddbb
 Creating MS object, TLLI = 0xffeeddbc
 Attaching TBF to MS object, TLLI = 0xffeeddbb, TBF = TBF(TFI=0 TLLI=0x00000000 DIR=UL STATE=NULL)
diff --git a/tests/ms/MsTest.ok b/tests/ms/MsTest.ok
index 219eec1..004b36d 100644
--- a/tests/ms/MsTest.ok
+++ b/tests/ms/MsTest.ok
@@ -8,5 +8,7 @@
   ms_active() was called
   ms_idle() was called
 === end test_ms_replace_tbf ===
+=== start test_ms_change_tlli ===
+=== end test_ms_change_tlli ===
 === start test_ms_storage ===
 === end test_ms_storage ===
diff --git a/tests/tbf/TbfTest.cpp b/tests/tbf/TbfTest.cpp
index d5bcb67..2ec715b 100644
--- a/tests/tbf/TbfTest.cpp
+++ b/tests/tbf/TbfTest.cpp
@@ -51,6 +51,8 @@
 static void test_tbf_tlli_update()
 {
 	BTS the_bts;
+	GprsMs *ms, *ms_new;
+
 	the_bts.bts_data()->alloc_algorithm = alloc_algorithm_a;
 	the_bts.bts_data()->trx[0].pdch[2].enable();
 	the_bts.bts_data()->trx[0].pdch[3].enable();
@@ -63,6 +65,7 @@
 						0, 0, 0);
 	dl_tbf->update_tlli(0x2342);
 	dl_tbf->tlli_mark_valid();
+	dl_tbf->update_ms(0x2342);
 	dl_tbf->ta = 4;
 	the_bts.timing_advance()->remember(0x2342, dl_tbf->ta);
 
@@ -71,23 +74,33 @@
 						0, 0, 0);
 	ul_tbf->update_tlli(0x2342);
 	ul_tbf->tlli_mark_valid();
-	
 
-	OSMO_ASSERT(the_bts.dl_tbf_by_tlli(0x2342) == dl_tbf);
-	OSMO_ASSERT(the_bts.ul_tbf_by_tlli(0x2342) == ul_tbf);
+	ms = the_bts.ms_by_tlli(0x2342);
 
+	OSMO_ASSERT(ms != NULL);
+	OSMO_ASSERT(ms->dl_tbf() == dl_tbf);
+	OSMO_ASSERT(ms->ul_tbf() == ul_tbf);
 
 	/*
 	 * Now check.. that DL changes and that the timing advance
 	 * has changed.
 	 */
 	dl_tbf->update_tlli(0x4232);
-	OSMO_ASSERT(!the_bts.dl_tbf_by_tlli(0x2342));
-	OSMO_ASSERT(!the_bts.ul_tbf_by_tlli(0x2342));
+	ms->confirm_tlli(0x4232);
 
-	
-	OSMO_ASSERT(the_bts.dl_tbf_by_tlli(0x4232) == dl_tbf);
-	OSMO_ASSERT(the_bts.ul_tbf_by_tlli(0x4232) == ul_tbf);
+	/* It is still there, since the new TLLI has not been used for UL yet */
+	ms_new = the_bts.ms_by_tlli(0x2342);
+	OSMO_ASSERT(ms == ms_new);
+
+	ms_new = the_bts.ms_by_tlli(0x4232);
+	OSMO_ASSERT(ms == ms_new);
+	OSMO_ASSERT(ms->dl_tbf() == dl_tbf);
+	OSMO_ASSERT(ms->ul_tbf() == ul_tbf);
+
+	/* Now use the new TLLI for UL */
+	ms->set_tlli(0x4232);
+	ms_new = the_bts.ms_by_tlli(0x2342);
+	OSMO_ASSERT(ms_new == NULL);
 
 	OSMO_ASSERT(the_bts.timing_advance()->recall(0x4232) == 4);
 }
@@ -318,7 +331,7 @@
 
 		snprintf(imsi, sizeof(imsi)-1, "001001%9d", i);
 
-		rc = gprs_rlcmac_dl_tbf::handle(bts, tlli, imsi, ms_class,
+		rc = gprs_rlcmac_dl_tbf::handle(bts, tlli, 0, imsi, ms_class,
 			delay_csec, buf, sizeof(buf));
 
 		if (rc < 0)
diff --git a/tests/tbf/TbfTest.err b/tests/tbf/TbfTest.err
index 3a58351..32f9efc 100644
--- a/tests/tbf/TbfTest.err
+++ b/tests/tbf/TbfTest.err
@@ -6,6 +6,8 @@
 - Assign downlink TS=2
 - Setting Control TS 2
 TBF(TFI=0 TLLI=0x00000000 DIR=DL STATE=NULL) changing tlli from TLLI=0x00000000 TLLI=0x00002342 ul_changed=0
+Creating MS object, TLLI = 0x00002342
+Attaching TBF to MS object, TLLI = 0x00002342, TBF = TBF(TFI=0 TLLI=0x00002342 DIR=DL STATE=NULL)
 ********** TBF starts here **********
 Allocating UL TBF: TFI=0 TRX=0 MS_CLASS=0
 Slot Allocation (Algorithm A) for class 0
@@ -13,8 +15,11 @@
 - Skipping TS 1, because not enabled
 - Assign uplink TS=2 USF=0
 - Setting Control TS 2
+Attaching TBF to MS object, TLLI = 0x00002342, TBF = TBF(TFI=0 TLLI=0x00000000 DIR=UL STATE=NULL)
 TBF(TFI=0 TLLI=0x00000000 DIR=UL STATE=NULL) changing tlli from TLLI=0x00000000 TLLI=0x00002342 ul_changed=0
-TBF(TFI=0 TLLI=0x00002342 DIR=DL STATE=NULL) changing tlli from TLLI=0x00002342 TLLI=0x00004232 ul_changed=1
+TBF(TFI=0 TLLI=0x00002342 DIR=DL STATE=NULL) changing tlli from TLLI=0x00002342 TLLI=0x00004232 ul_changed=0
+The MS object cannot fully confirm an unexpected TLLI: 0x00004232, partly confirmed
+Modifying MS object, TLLI: 0x00002342 -> 0x00004232, already confirmed partly
 Searching for first unallocated TFI: TRX=0 first TS=4
  Found TFI=0.
 ********** TBF starts here **********