diff --git a/libs/ardour/ardour/region.h b/libs/ardour/ardour/region.h
index 0675583ee4..859df381b0 100644
--- a/libs/ardour/ardour/region.h
+++ b/libs/ardour/ardour/region.h
@@ -115,6 +115,7 @@ public:
 	const DataType& data_type () const { return _type; }
 	Temporal::TimeDomain time_domain() const;
 	virtual void globally_change_time_domain (Temporal::TimeDomain from, Temporal::TimeDomain to);
+	virtual void change_time_domain (Temporal::TimeDomain from, Temporal::TimeDomain to);
 
 	/** How the region parameters play together:
 	 *
diff --git a/libs/ardour/ardour/utils.h b/libs/ardour/ardour/utils.h
index e180ae510d..37788b321e 100644
--- a/libs/ardour/ardour/utils.h
+++ b/libs/ardour/ardour/utils.h
@@ -124,8 +124,8 @@ template<typename T> std::shared_ptr<AutomationControlList> route_list_to_contro
 	return cl;
 }
 
-template<typename T> std::shared_ptr<ControlList> stripable_list_to_control_list (StripableList& sl, std::shared_ptr<T> (Stripable::*get_control)() const) {
-	std::shared_ptr<ControlList> cl (new ControlList);
+template<typename T> std::shared_ptr<AutomationControlList> stripable_list_to_control_list (StripableList& sl, std::shared_ptr<T> (Stripable::*get_control)() const) {
+	std::shared_ptr<AutomationControlList> cl (new AutomationControlList);
 	for (auto const & s : sl) {
 		std::shared_ptr<AutomationControl> ac = (s.get()->*get_control)();
 		if (ac) {
@@ -135,8 +135,8 @@ template<typename T> std::shared_ptr<ControlList> stripable_list_to_control_list
 	return cl;
 }
 
-template<typename T> std::shared_ptr<ControlList> stripable_list_to_control_list (std::shared_ptr<StripableList const> sl, std::shared_ptr<T> (Stripable::*get_control)() const) {
-	std::shared_ptr<ControlList> cl (new ControlList);
+template<typename T> std::shared_ptr<AutomationControlList> stripable_list_to_control_list (std::shared_ptr<StripableList const> sl, std::shared_ptr<T> (Stripable::*get_control)() const) {
+	std::shared_ptr<AutomationControlList> cl (new AutomationControlList);
 	for (auto const & s : *sl) {
 		std::shared_ptr<AutomationControl> ac = (s.get()->*get_control)();
 		if (ac) {
diff --git a/libs/ardour/location.cc b/libs/ardour/location.cc
index 1c290d2db9..8b2017ac9e 100644
--- a/libs/ardour/location.cc
+++ b/libs/ardour/location.cc
@@ -783,17 +783,11 @@ Location::globally_change_time_domain (Temporal::TimeDomain from, Temporal::Time
 
 	if (_start.time_domain() == from) {
 
-		std::cerr << "switching location [" << name() << "] from " << _start;
-
 		_start.set_time_domain (to);
 		_end.set_time_domain (to);
 
-		std::cerr << " to " << _start << std::endl;
-
 		domain_swap->add (_start);
 		domain_swap->add (_end);
-	} else {
-		std::cerr << name() << " wrong domain: " << _start << " .. " << _end << std::endl;
 	}
 }
 
diff --git a/libs/ardour/region.cc b/libs/ardour/region.cc
index bce89ec1b5..902efff5d8 100644
--- a/libs/ardour/region.cc
+++ b/libs/ardour/region.cc
@@ -2251,12 +2251,14 @@ Region::globally_change_time_domain (Temporal::TimeDomain from, Temporal::TimeDo
 {
 	assert (Temporal::domain_swap);
 
+	/* recall that the _length member is a timecnt_t, and so holds both
+	 * position *and* length.
+	 */
+
 	if (_length.val().time_domain() == from) {
 		timecnt_t& l (_length.non_const_val());
-		std::cerr << "old domain after GCTD " << _length.val() << std::endl;
 		l.set_time_domain (to);
 		Temporal::domain_swap->add (l);
-		std::cerr << "new domain after GCTD " << _length.val() << std::endl;
 	}
 }
 
diff --git a/libs/ardour/session_time.cc b/libs/ardour/session_time.cc
index db61df1d06..b98d1d9d08 100644
--- a/libs/ardour/session_time.cc
+++ b/libs/ardour/session_time.cc
@@ -302,8 +302,6 @@ Session::any_duration_to_samples (samplepos_t position, AnyTime const & duration
 void
 Session::globally_change_time_domain (Temporal::TimeDomain from, Temporal::TimeDomain to)
 {
-	std::cerr << "GCTD from " << from << " to " << to << std::endl;
-
 	{
 		std::shared_ptr<RouteList const> rl (routes.reader());