diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index 2b90a6e44..5d65a665e 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -9649,7 +9649,9 @@ private function f_vty_set_imm_ass(TELNETasp_PT pt, BtsNr bts_nr := 0, charstrin
 }
 
 private function f_verify_imm_ass(RSL_Message imm_ass, template uint8_t ra := ?, template GsmFrameNumber fn := ?,
-				  template RslChannelNr chan_nr := ?)
+				  template RslChannelNr chan_nr := ?,
+				  template (present) uint12_t arfcn := ?,
+				  template (present) uint3_t tsc := ?)
 {
 	var RSL_IE_Body full_imm_ass_info;
 	if (not f_rsl_find_ie(imm_ass, RSL_IE_FULL_IMM_ASS_INFO, full_imm_ass_info)) {
@@ -9660,7 +9662,7 @@ private function f_verify_imm_ass(RSL_Message imm_ass, template uint8_t ra := ?,
 	var GsmRrMessage rr_imm_ass := dec_GsmRrMessage(full_imm_ass_info.full_imm_ass_info.payload);
 	var template GsmRrMessage expect_imm_ass := tr_IMM_ASS(ra := ra,
 							       fn := fn,
-							       ch_desc := tr_ChanDescH0(chan_nr),
+							       ch_desc := tr_ChanDescH0(chan_nr, arfcn, tsc),
 							       page_mode := ?);
 	if (not match(rr_imm_ass, expect_imm_ass)) {
 		log("Error: expected ", expect_imm_ass, " got ", rr_imm_ass);
@@ -9688,12 +9690,19 @@ testcase TC_imm_ass_post_chan_ack() runs on test_CT {
 
 	/* First send the Chan Act ACK */
 	var RslChannelNr chan_nr := chan_act.ies[0].body.chan_nr;
+	var RSL_IE_Body chan_ident_ie;
+	if (not f_rsl_find_ie(chan_act, RSL_IE_CHAN_IDENT, chan_ident_ie)) {
+		setverdict(fail, "RSL Channel Identification IE is absent");
+		mtc.stop;
+	}
+
 	f_ipa_tx(0, ts_RSL_CHAN_ACT_ACK(chan_nr, fn + 10));
 
 	/* Then expect the Immediate Assignment, after we ACKed the chan act */
 	imm_ass := f_exp_ipa_rx(0, tr_RSL_IMM_ASSIGN(0));
 
-	f_verify_imm_ass(imm_ass, ra, fn, chan_nr);
+	f_verify_imm_ass(imm_ass, ra, fn, chan_nr, chan_ident_ie.chan_ident.ch_desc.v.arfcn,
+			 chan_ident_ie.chan_ident.ch_desc.v.tsc);
 
 	/* Check that the lchan is working */
 	var octetstring l3 := '00010203040506'O;
@@ -9726,10 +9735,16 @@ testcase TC_imm_ass_pre_chan_ack() runs on test_CT {
 
 	chan_act := f_exp_ipa_rx(0, tr_RSL_MsgTypeD(RSL_MT_CHAN_ACTIV));
 	var RslChannelNr chan_nr := chan_act.ies[0].body.chan_nr;
+	var RSL_IE_Body chan_ident_ie;
+	if (not f_rsl_find_ie(chan_act, RSL_IE_CHAN_IDENT, chan_ident_ie)) {
+		setverdict(fail, "RSL Channel Identification IE is absent");
+		mtc.stop;
+	}
 
 	/* *FIRST* expect the Immediate Assignment, before we ACK the chan act */
 	imm_ass := f_exp_ipa_rx(0, tr_RSL_IMM_ASSIGN(0));
-	f_verify_imm_ass(imm_ass, ra, fn, chan_nr);
+	f_verify_imm_ass(imm_ass, ra, fn, chan_nr, chan_ident_ie.chan_ident.ch_desc.v.arfcn,
+			 chan_ident_ie.chan_ident.ch_desc.v.tsc);
 
 	/* Only now send the Chan Act ACK */
 	f_ipa_tx(0, ts_RSL_CHAN_ACT_ACK(chan_nr, fn+10));
@@ -9792,10 +9807,16 @@ testcase TC_imm_ass_pre_chan_ack_dyn_ts() runs on test_CT {
 	chan_nr := valueof(t_RslChanNr_SDCCH8(tn := 6, sub_slot := 0));
 
 	chan_act := f_exp_ipa_rx(0, tr_RSL_MsgTypeD(RSL_MT_CHAN_ACTIV));
+	var RSL_IE_Body chan_ident_ie;
+	if (not f_rsl_find_ie(chan_act, RSL_IE_CHAN_IDENT, chan_ident_ie)) {
+		setverdict(fail, "RSL Channel Identification IE is absent");
+		mtc.stop;
+	}
 
 	/* *FIRST* expect the Immediate Assignment, before we ACK the chan act */
 	imm_ass := f_exp_ipa_rx(0, tr_RSL_IMM_ASSIGN(0));
-	f_verify_imm_ass(imm_ass, ra, fn, chan_nr);
+	f_verify_imm_ass(imm_ass, ra, fn, chan_nr, chan_ident_ie.chan_ident.ch_desc.v.arfcn,
+			 chan_ident_ie.chan_ident.ch_desc.v.tsc);
 
 	/* Only now send the Chan Act ACK */
 	f_ipa_tx(0, ts_RSL_CHAN_ACT_ACK(chan_nr, fn+10));
@@ -9863,9 +9884,15 @@ testcase TC_imm_ass_pre_ts_ack_dyn_ts() runs on test_CT {
 	chan_nr := valueof(t_RslChanNr_SDCCH8(tn := 6, sub_slot := 0));
 
 	chan_act := f_exp_ipa_rx(0, tr_RSL_MsgTypeD(RSL_MT_CHAN_ACTIV));
+	var RSL_IE_Body chan_ident_ie;
+	if (not f_rsl_find_ie(chan_act, RSL_IE_CHAN_IDENT, chan_ident_ie)) {
+		setverdict(fail, "RSL Channel Identification IE is absent");
+		mtc.stop;
+	}
 	f_ipa_tx(0, ts_RSL_CHAN_ACT_ACK(chan_nr, fn+10));
 
-	f_verify_imm_ass(imm_ass, ra, fn, chan_nr);
+	f_verify_imm_ass(imm_ass, ra, fn, chan_nr, chan_ident_ie.chan_ident.ch_desc.v.arfcn,
+			 chan_ident_ie.chan_ident.ch_desc.v.tsc);
 
 	/* Check that the lchan is working */
 	var octetstring l3 := '00010203040506'O;