diff --git a/gtk2_ardour/audio_clock.cc b/gtk2_ardour/audio_clock.cc
index 2718fc7542..19008165ad 100644
--- a/gtk2_ardour/audio_clock.cc
+++ b/gtk2_ardour/audio_clock.cc
@@ -2123,7 +2123,7 @@ AudioClock::samples_from_bbt_string (timepos_t const & pos, const string& str) c
 		return 0;
 	}
 
-	BBT_Time bbt;
+	BBT_Argument bbt;
 
 	if (sscanf (str.c_str(), BBT_SCANF_FORMAT, &bbt.bars, &bbt.beats, &bbt.ticks) != 3) {
 		return 0;
diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index aa42c9f496..272ddf0ac1 100644
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -2957,16 +2957,16 @@ Editor::snap_to_bbt (timepos_t const & presnap, Temporal::RoundMode direction, S
 
 	if (_grid_type == GridTypeBar) {
 		TempoMetric m (tmap->metric_at (presnap));
-		BBT_Time bbt (m.bbt_at (presnap));
+		BBT_Argument bbt (m.bbt_at (presnap));
 		switch (direction) {
 		case RoundDownAlways:
-			bbt = bbt.round_down_to_bar ();
+			bbt = BBT_Argument (bbt.reference(), bbt.round_down_to_bar ());
 			break;
 		case RoundUpAlways:
-			bbt = bbt.round_up_to_bar ();
+			bbt = BBT_Argument (bbt.reference(), bbt.round_up_to_bar ());
 			break;
 		case RoundNearest:
-			bbt = m.round_to_bar (bbt);
+			bbt = BBT_Argument (bbt.reference(), m.round_to_bar (bbt));
 			break;
 		default:
 			break;
diff --git a/gtk2_ardour/editor_audio_import.cc b/gtk2_ardour/editor_audio_import.cc
index 650f236111..a86686a1df 100644
--- a/gtk2_ardour/editor_audio_import.cc
+++ b/gtk2_ardour/editor_audio_import.cc
@@ -310,7 +310,7 @@ Editor::import_smf_tempo_map (Evoral::SMF const & smf, timepos_t const & pos)
 		cerr << "new meter from SMF : " << meter << endl;
 
 
-		Temporal::BBT_Time bbt; /* 1|1|0 which is correct for the no-meter case */
+		Temporal::BBT_Argument bbt; /* 1|1|0 which is correct for the no-meter case */
 
 		if (have_initial_meter) {
 
diff --git a/gtk2_ardour/editor_tempodisplay.cc b/gtk2_ardour/editor_tempodisplay.cc
index db5654dded..7f12b15391 100644
--- a/gtk2_ardour/editor_tempodisplay.cc
+++ b/gtk2_ardour/editor_tempodisplay.cc
@@ -519,9 +519,9 @@ Editor::mouse_add_new_meter_event (timepos_t pos)
 
 	double note_type = meter_dialog.get_note_type ();
 
-	Temporal::BBT_Time requested;
-	meter_dialog.get_bbt_time (requested);
-
+	Temporal::BBT_Time r;
+	meter_dialog.get_bbt_time (r);
+	Temporal::BBT_Argument requested (timepos_t::zero (Temporal::BeatTime), r);
 
 	TempoMapChange tmc (*this, _("add time signature"));
 	pos = timepos_t (tmc.map().quarters_at (requested));
@@ -631,8 +631,9 @@ Editor::edit_meter_section (Temporal::MeterPoint& section)
 	double const note_type = meter_dialog.get_note_type ();
 	const Meter meter (bpb, note_type);
 
-	Temporal::BBT_Time when;
-	meter_dialog.get_bbt_time (when);
+	Temporal::BBT_Time w;
+	meter_dialog.get_bbt_time (w);
+	Temporal::BBT_Argument when (timepos_t::zero (Temporal::BeatTime), w);
 
 	TempoMapChange tmc (*this, _("edit time signature"));
 	tmc.map().set_meter (meter, when);
@@ -682,8 +683,9 @@ Editor::edit_tempo_section (TempoPoint& section)
 
 	const Tempo tempo (bpm, end_bpm, nt);
 
-	Temporal::BBT_Time when;
-	tempo_dialog.get_bbt_time (when);
+	Temporal::BBT_Time w;
+	tempo_dialog.get_bbt_time (w);
+	Temporal::BBT_Argument when (timepos_t::zero (Temporal::BeatTime), w);
 
 	TempoMapChange tmc (*this, _("edit tempo"));
 	tmc.map().replace_tempo (section, tempo, timepos_t (tmc.map().quarters_at (when)));
diff --git a/gtk2_ardour/step_editor.cc b/gtk2_ardour/step_editor.cc
index 511d2340ef..a8e3748115 100644
--- a/gtk2_ardour/step_editor.cc
+++ b/gtk2_ardour/step_editor.cc
@@ -420,7 +420,7 @@ StepEditor::step_edit_bar_sync ()
 
 	/* have to go to BBT to round up to bar, unfortunately */
 	TempoMap::SharedPtr tmap (TempoMap::use());
-	BBT_Time bbt (tmap->bbt_at (pos).round_up_to_bar ());
+	BBT_Argument bbt (tmap->bbt_at (pos).round_up_to_bar ());
 
 	/* now back to beats */
 	pos = timepos_t (tmap->quarters_at (bbt));
diff --git a/gtk2_ardour/tempo_dialog.cc b/gtk2_ardour/tempo_dialog.cc
index 36cba7ea55..1449c51f46 100644
--- a/gtk2_ardour/tempo_dialog.cc
+++ b/gtk2_ardour/tempo_dialog.cc
@@ -608,7 +608,7 @@ TempoDialog::tap_tempo_focus_out (GdkEventFocus* )
 MeterDialog::MeterDialog (TempoMap::SharedPtr const & map, timepos_t const & pos, const string&)
 	: ArdourDialog (_("New Time Signature"))
 {
-	Temporal::BBT_Time when (map->round_to_bar (map->bbt_at (pos)));
+	Temporal::BBT_Argument when (map->round_to_bar (map->bbt_at (pos)));
 	Meter const & meter (map->meter_at (when));
 
 	init (when, meter.divisions_per_bar(), meter.note_value(), false, pos.time_domain());