diff --git a/library/RLCMAC_Types.ttcn b/library/RLCMAC_Types.ttcn
index 8e6942e61..3a1ecb103 100644
--- a/library/RLCMAC_Types.ttcn
+++ b/library/RLCMAC_Types.ttcn
@@ -31,6 +31,16 @@ module RLCMAC_Types {
 		RRBP_Nplus26_mod_2715648	('11'B)
 	} with { variant "FIELDLENGTH(2)" };
 
+	function f_rrbp_fn_delay(MacRrbp rrbp) return uint32_t {
+		select (rrbp) {
+		case (RRBP_Nplus13_mod_2715648) { return 13; }
+		case (RRBP_Nplus17_or_18_mod_2715648) { return 17; }
+		case (RRBP_Nplus21_or_22_mod_2715648) { return 21;  }
+		case (RRBP_Nplus26_mod_2715648) { return 26; }
+		}
+		return 0;
+	}
+
 	/* Partof DL RLC data block and DL RLC/MAC ctrl block */
 	type record DlMacHeader {
 		MacPayloadType	payload_type,
diff --git a/pcu/PCUIF_RAW_Components.ttcn b/pcu/PCUIF_RAW_Components.ttcn
index 5516d8312..4ed57e572 100644
--- a/pcu/PCUIF_RAW_Components.ttcn
+++ b/pcu/PCUIF_RAW_Components.ttcn
@@ -228,6 +228,18 @@ private function f_PCUIF_MsgQueue_dequeue(inout PCUIF_MsgQueue queue,
 	}
 }
 
+/* Get first message from queue. true if non-empty, false otherwise */
+private function f_PCUIF_MsgQueue_first(inout PCUIF_MsgQueue queue,
+					out PCUIF_Message msg) return boolean
+{
+	if (lengthof(queue) == 0) {
+		return false;
+	}
+
+	msg := queue[0];
+	return true;
+}
+
 /* Multiple base stations can be connected to the PCU. This component
  * represents one BTS with an associated TDMA clock generator. */
 type component RAW_PCU_BTS_CT {
@@ -250,6 +262,9 @@ type component RAW_PCU_BTS_CT {
 	var boolean cfg_ptcch_burst_fwd := false;
 }
 
+/* Queue received messages from Test Case, they will eventually be scheduled and
+ * sent according to their FN. FN value of 0 has the special meaning of "schedule
+ * as soon as possible". */
 private altstep as_BTS_CT_MsgQueue(integer bts_nr)
 runs on RAW_PCU_BTS_CT {
 	var PCUIF_Message pcu_msg;
@@ -274,11 +289,14 @@ runs on RAW_PCU_BTS_CT {
 		}
 }
 
+/* Handle schedule events and manage actions: Send msgs over PCUIF to PCU,
+ * advertise Test Case about sent messages, etc. */
 private altstep as_BTS_CT_TDMASched(integer bts_nr)
 runs on RAW_PCU_BTS_CT {
 	var PCUIF_Message pcu_msg;
 	var RAW_PCU_Event event;
 	var integer ev_begin_fn;
+	var integer next_fn;
 
 	[] CLCK.receive(tr_RAW_PCU_EV(TDMA_EV_PDTCH_BLOCK_BEG)) -> value event {
 		/* If the RTS queue for PDTCH is not empty, send a message */
@@ -299,6 +317,17 @@ runs on RAW_PCU_BTS_CT {
 	[lengthof(pdtch_data_queue) > 0] CLCK.receive(tr_RAW_PCU_EV(TDMA_EV_PDTCH_BLOCK_END)) -> value event {
 		/* FN matching the beginning of current block: */
 		ev_begin_fn := event.data.tdma_fn - 3;
+
+		/* Check if we reached time to serve the first DATA.ind message in the queue: */
+		f_PCUIF_MsgQueue_first(pdtch_data_queue, pcu_msg);
+		next_fn := pcu_msg.u.data_ind.fn;
+		if (next_fn != 0 and next_fn != ev_begin_fn) {
+			if (next_fn < ev_begin_fn) {
+				setverdict(fail, "We are late scheduling the block! ", next_fn, " < ", ev_begin_fn);
+				mtc.stop;
+			}
+			repeat;
+		}
 		/* Dequeue a DATA.ind message */
 		f_PCUIF_MsgQueue_dequeue(pdtch_data_queue, pcu_msg);
 
diff --git a/pcu/PCU_Tests_RAW.ttcn b/pcu/PCU_Tests_RAW.ttcn
index cddf9f667..e4b03c1f9 100644
--- a/pcu/PCU_Tests_RAW.ttcn
+++ b/pcu/PCU_Tests_RAW.ttcn
@@ -663,13 +663,16 @@ runs on RAW_PCU_Test_CT return boolean {
 }
 
 /* Enqueue DATA.ind (both TDMA frame and block numbers to be patched) */
-private function f_pcuif_tx_data_ind(octetstring data, int16_t lqual_cb := 0)
+private function f_pcuif_tx_data_ind(octetstring data, int16_t lqual_cb := 0, uint32_t fn := 0)
 runs on RAW_PCU_Test_CT {
-
+	var template RAW_PCU_EventParam ev_param := {tdma_fn := ? };
 	BTS.send(ts_PCUIF_DATA_IND(bts_nr := 0, trx_nr := 0, ts_nr := 7, block_nr := 0,
 				   sapi := PCU_IF_SAPI_PDTCH, data := data,
-				   fn := 0, arfcn := 871, lqual_cb := lqual_cb));
-	BTS.receive(tr_RAW_PCU_EV(TDMA_EV_PDTCH_BLOCK_SENT));
+				   fn := fn, arfcn := 871, lqual_cb := lqual_cb));
+	if (fn != 0) {
+		ev_param := {tdma_fn := fn };
+	}
+	BTS.receive(tr_RAW_PCU_EV(TDMA_EV_PDTCH_BLOCK_SENT, ev_param));
 }
 
 /* Enqueue RTS.req, expect DATA.req with UL ACK from the PCU */
@@ -700,7 +703,7 @@ runs on RAW_PCU_Test_CT {
 				   fn := 0, arfcn := 871, sapi := PCU_IF_SAPI_PCH, data := macblock));
 }
 
-private function f_tx_rlcmac_ul_block(template (value) RlcmacUlBlock ul_data, int16_t lqual_cb := 0)
+private function f_tx_rlcmac_ul_block(template (value) RlcmacUlBlock ul_data, int16_t lqual_cb := 0, uint32_t fn := 0)
 runs on RAW_PCU_Test_CT {
 	var octetstring data;
 	/* Encode the payload of DATA.ind */
@@ -708,7 +711,7 @@ runs on RAW_PCU_Test_CT {
 	data := f_pad_oct(data, 23, '00'O); /* CS-1 */
 
 	/* Enqueue DATA.ind (both TDMA frame and block numbers to be patched) */
-	f_pcuif_tx_data_ind(data, lqual_cb);
+	f_pcuif_tx_data_ind(data, lqual_cb, fn);
 }
 
 private function f_tx_rlcmac_ul_n_blocks(PacketUlAssign ul_tbf_ass, integer num_blocks := 1)
@@ -730,16 +733,19 @@ runs on RAW_PCU_Test_CT {
 	}
 }
 
-private function f_rx_rlcmac_dl_block(out RlcmacDlBlock dl_block)
+private function f_rx_rlcmac_dl_block(out RlcmacDlBlock dl_block, out uint32_t dl_fn)
 runs on RAW_PCU_Test_CT {
 	var PCUIF_Message pcu_msg;
 	f_pcuif_rx_data_req(pcu_msg);
 	dl_block := dec_RlcmacDlBlock(pcu_msg.u.data_req.data);
+	dl_fn := pcu_msg.u.data_req.fn;
 }
 
 private function f_rx_rlcmac_dl_block_exp_ack_nack(out RlcmacDlBlock dl_block)
 runs on RAW_PCU_Test_CT {
-	f_rx_rlcmac_dl_block(dl_block);
+	var uint32_t dl_fn;
+
+	f_rx_rlcmac_dl_block(dl_block, dl_fn);
 	if (not match(dl_block, tr_RLCMAC_UL_ACK_NACK(ul_tfi := ?, tlli := ?))) {
 		setverdict(fail, "Failed to match Packet Uplink ACK / NACK");
 		mtc.stop;
@@ -748,24 +754,30 @@ runs on RAW_PCU_Test_CT {
 
 private function f_rx_rlcmac_dl_block_exp_dummy(out RlcmacDlBlock dl_block)
 runs on RAW_PCU_Test_CT {
-	f_rx_rlcmac_dl_block(dl_block);
+	var uint32_t dl_fn;
+
+	f_rx_rlcmac_dl_block(dl_block, dl_fn);
 	if (not match(dl_block, tr_RLCMAC_DUMMY_CTRL())) {
 		setverdict(fail, "Failed to match Packet DUMMY DL");
 		mtc.stop;
 	}
 }
 
-private function f_rx_rlcmac_dl_block_exp_data(out RlcmacDlBlock dl_block, octetstring data)
+private function f_rx_rlcmac_dl_block_exp_data(out RlcmacDlBlock dl_block, out uint32_t ack_fn, octetstring data)
 runs on RAW_PCU_Test_CT {
+	var PCUIF_Message pcu_msg;
+	var uint32_t dl_fn;
 	var template RlcmacDlBlock dl_template := tr_RLCMAC_DATA_RRBP;
 	dl_template.data.blocks := ?;
 
-	f_rx_rlcmac_dl_block(dl_block);
+	f_rx_rlcmac_dl_block(dl_block, dl_fn);
 	if (not match(dl_block, dl_template)) {
 		setverdict(fail, "Failed to match Packet data: ", dl_block, " vs ", dl_template);
 		mtc.stop;
 	}
 
+	ack_fn := dl_fn + f_rrbp_fn_delay(dl_block.data.mac_hdr.mac_hdr.rrbp);
+
 	if (lengthof(dl_block.data.blocks) < 1) {
 		setverdict(fail, "DL block has no LLC payload: ", dl_block);
 		mtc.stop;
@@ -1358,6 +1370,7 @@ testcase TC_mo_ping_pong() runs on RAW_PCU_Test_CT {
 	var PCUIF_Message pcu_msg;
 	var octetstring data := f_rnd_octstring(10);
 	var boolean ok;
+	var uint32_t sched_fn;
 	var OCT4 tlli := '00000001'O;
 	var AckNackDescription ack_nack_desc;
 
@@ -1407,10 +1420,10 @@ testcase TC_mo_ping_pong() runs on RAW_PCU_Test_CT {
 
 	/* Wait timer X2002 and DL block is available after CCCH IMM ASS: */
 	f_sleep(X2002);
-	f_rx_rlcmac_dl_block_exp_data(dl_block, data);
+	f_rx_rlcmac_dl_block_exp_data(dl_block, sched_fn, data);
 
 	/* ACK the DL block */
-	f_tx_rlcmac_ul_block(ts_RLCMAC_DL_ACK_NACK(dl_block.data.mac_hdr.hdr_ext.tfi, ack_nack_desc));
+	f_tx_rlcmac_ul_block(ts_RLCMAC_DL_ACK_NACK(dl_block.data.mac_hdr.hdr_ext.tfi, ack_nack_desc), 0, sched_fn);
 }
 
 control {