diff --git a/world/expedition.cpp b/world/expedition.cpp
index 1d30fcd67..eecd91559 100644
--- a/world/expedition.cpp
+++ b/world/expedition.cpp
@@ -39,10 +39,10 @@ Expedition::Expedition(
 	m_expedition_id(expedition_id),
 	m_dz_instance_id(instance_id),
 	m_dz_zone_id(dz_zone_id),
-	m_start_time(start_time),
+	m_start_time(std::chrono::system_clock::from_time_t(start_time)),
 	m_duration(duration)
 {
-	m_expire_time = std::chrono::system_clock::from_time_t(m_start_time + m_duration);
+	m_expire_time = m_start_time + m_duration;
 }
 
 void Expedition::SendZonesExpeditionDeleted()
@@ -60,7 +60,7 @@ void Expedition::SendZonesDurationUpdate()
 	auto pack = std::unique_ptr<ServerPacket>(new ServerPacket(ServerOP_ExpeditionDzDuration, packsize));
 	auto packbuf = reinterpret_cast<ServerExpeditionUpdateDuration_Struct*>(pack->pBuffer);
 	packbuf->expedition_id = GetID();
-	packbuf->new_duration_seconds = m_duration;
+	packbuf->new_duration_seconds = static_cast<uint32_t>(m_duration.count());
 	zoneserver_list.SendPacket(pack.get());
 }
 
@@ -78,12 +78,10 @@ void Expedition::UpdateDzSecondsRemaining(uint32_t seconds_remaining)
 		);
 
 		// preserve original start time and adjust duration instead
-		auto new_expire_time = now + update_time;
-		auto new_duration = std::chrono::system_clock::to_time_t(new_expire_time) - m_start_time;
-		m_duration = static_cast<uint32_t>(new_duration);
-		m_expire_time = std::chrono::system_clock::from_time_t(m_start_time + m_duration);
+		m_expire_time = now + update_time;
+		m_duration = std::chrono::duration_cast<std::chrono::seconds>(m_expire_time - m_start_time);
 
-		ExpeditionDatabase::UpdateDzDuration(GetInstanceID(), m_duration);
+		ExpeditionDatabase::UpdateDzDuration(GetInstanceID(), static_cast<uint32_t>(m_duration.count()));
 
 		// update zone level caches and update the actual dz instance's timer
 		SendZonesDurationUpdate();
diff --git a/world/expedition.h b/world/expedition.h
index a933e5d9d..8f14a334d 100644
--- a/world/expedition.h
+++ b/world/expedition.h
@@ -93,10 +93,10 @@ private:
 	uint32_t m_expedition_id  = 0;
 	uint32_t m_dz_instance_id = 0;
 	uint32_t m_dz_zone_id     = 0;
-	uint32_t m_start_time     = 0;
-	uint32_t m_duration       = 0;
 	bool     m_pending_delete = false;
 	std::unordered_set<uint32_t> m_member_ids;
+	std::chrono::seconds m_duration;
+	std::chrono::time_point<std::chrono::system_clock> m_start_time;
 	std::chrono::time_point<std::chrono::system_clock> m_expire_time;
 };
 
diff --git a/zone/dynamiczone.cpp b/zone/dynamiczone.cpp
index 362f70140..65f92e321 100644
--- a/zone/dynamiczone.cpp
+++ b/zone/dynamiczone.cpp
@@ -119,14 +119,15 @@ uint32_t DynamicZone::CreateInstance()
 		return 0;
 	}
 
-	auto start_time = std::chrono::system_clock::to_time_t(std::chrono::system_clock::now());
+	m_start_time    = std::chrono::system_clock::now();
+	auto start_time = std::chrono::system_clock::to_time_t(m_start_time);
 
 	std::string query = fmt::format(SQL(
 		INSERT INTO instance_list
 			(id, zone, version, start_time, duration)
 		VALUES
 			({}, {}, {}, {}, {})
-	), instance_id, m_zone_id, m_version, start_time, m_duration);
+	), instance_id, m_zone_id, m_version, start_time, m_duration.count());
 
 	auto results = database.QueryDatabase(query);
 	if (!results.Success())
@@ -136,9 +137,8 @@ uint32_t DynamicZone::CreateInstance()
 	}
 
 	m_instance_id   = instance_id;
-	m_start_time    = static_cast<uint32_t>(start_time);
 	m_never_expires = false;
-	m_expire_time   = std::chrono::system_clock::from_time_t(m_start_time + m_duration);
+	m_expire_time   = m_start_time + m_duration;
 
 	return m_instance_id;
 }
@@ -178,11 +178,11 @@ void DynamicZone::LoadDatabaseResult(MySQLRequestRow& row)
 	m_instance_id        = strtoul(row[0], nullptr, 10);
 	m_zone_id            = strtoul(row[1], nullptr, 10);
 	m_version            = strtoul(row[2], nullptr, 10);
-	m_start_time         = strtoul(row[3], nullptr, 10);
-	m_duration           = strtoul(row[4], nullptr, 10);
+	m_start_time         = std::chrono::system_clock::from_time_t(strtoul(row[3], nullptr, 10));
+	m_duration           = std::chrono::seconds(strtoul(row[4], nullptr, 10));
+	m_expire_time        = m_start_time + m_duration;
 	m_never_expires      = (strtoul(row[5], nullptr, 10) != 0);
 	m_type               = static_cast<DynamicZoneType>(strtoul(row[6], nullptr, 10));
-	m_expire_time        = std::chrono::system_clock::from_time_t(m_start_time + m_duration);
 	m_compass.zone_id    = strtoul(row[7], nullptr, 10);
 	m_compass.x          = strtof(row[8], nullptr);
 	m_compass.y          = strtof(row[9], nullptr);
@@ -530,8 +530,8 @@ uint32_t DynamicZone::GetSecondsRemaining() const
 void DynamicZone::SetUpdatedDuration(uint32_t new_duration)
 {
 	// preserves original start time, just modifies duration and expire time
-	m_duration = new_duration;
-	m_expire_time = std::chrono::system_clock::from_time_t(m_start_time + m_duration);
+	m_duration = std::chrono::seconds(new_duration);
+	m_expire_time = m_start_time + m_duration;
 
 	if (zone && IsCurrentZoneDzInstance())
 	{
diff --git a/zone/dynamiczone.h b/zone/dynamiczone.h
index 83063d207..6951fe517 100644
--- a/zone/dynamiczone.h
+++ b/zone/dynamiczone.h
@@ -110,14 +110,14 @@ private:
 	uint32_t m_zone_id       = 0;
 	uint32_t m_instance_id   = 0;
 	uint32_t m_version       = 0;
-	uint32_t m_start_time    = 0;
-	uint32_t m_duration      = 0;
 	bool     m_never_expires = false;
 	bool     m_has_zonein    = false;
 	DynamicZoneType m_type   = DynamicZoneType::None;
 	DynamicZoneLocation m_compass;
 	DynamicZoneLocation m_safereturn;
 	DynamicZoneLocation m_zonein;
+	std::chrono::seconds m_duration;
+	std::chrono::time_point<std::chrono::system_clock> m_start_time;
 	std::chrono::time_point<std::chrono::system_clock> m_expire_time;
 };
 
diff --git a/zone/expedition_lockout_timer.cpp b/zone/expedition_lockout_timer.cpp
index e7eb8ea76..25743df8d 100644
--- a/zone/expedition_lockout_timer.cpp
+++ b/zone/expedition_lockout_timer.cpp
@@ -26,11 +26,12 @@
 const char* const DZ_REPLAY_TIMER_NAME = "Replay Timer"; // see December 14, 2016 patch notes
 
 ExpeditionLockoutTimer::ExpeditionLockoutTimer(
-	std::string expedition_name, std::string event_name, uint64_t expire_time, uint32_t duration, bool inherited
+	std::string expedition_name, std::string event_name,
+	uint64_t expire_time, uint32_t duration, bool inherited
 ) :
 	m_expedition_name(expedition_name),
 	m_event_name(event_name),
-	m_expire_time(expire_time),
+	m_expire_time(std::chrono::system_clock::from_time_t(expire_time)),
 	m_duration(duration),
 	m_is_inherited(inherited)
 {
@@ -43,11 +44,10 @@ ExpeditionLockoutTimer::ExpeditionLockoutTimer(
 uint32_t ExpeditionLockoutTimer::GetSecondsRemaining() const
 {
 	auto now = std::chrono::system_clock::now();
-	auto expire_time = std::chrono::system_clock::from_time_t(m_expire_time);
-	if (expire_time > now)
+	if (m_expire_time > now)
 	{
-		auto time_remaining = std::chrono::duration_cast<std::chrono::seconds>(expire_time - now).count();
-		return static_cast<uint32_t>(time_remaining);
+		auto remaining = m_expire_time - now;
+		return static_cast<uint32_t>(std::chrono::duration_cast<std::chrono::seconds>(remaining).count());
 	}
 	return 0;
 }
diff --git a/zone/expedition_lockout_timer.h b/zone/expedition_lockout_timer.h
index 45155a111..abd455ff5 100644
--- a/zone/expedition_lockout_timer.h
+++ b/zone/expedition_lockout_timer.h
@@ -21,6 +21,7 @@
 #ifndef EXPEDITION_LOCKOUT_TIMER_H
 #define EXPEDITION_LOCKOUT_TIMER_H
 
+#include <chrono>
 #include <string>
 
 extern const char* const DZ_REPLAY_TIMER_NAME;
@@ -29,7 +30,9 @@ class ExpeditionLockoutTimer
 {
 public:
 	ExpeditionLockoutTimer() {}
-	ExpeditionLockoutTimer(std::string expedition_name, std::string event_name, uint64_t expire_time, uint32_t duration, bool inherited = false);
+	ExpeditionLockoutTimer(
+		std::string expedition_name, std::string event_name,
+		uint64_t expire_time, uint32_t duration, bool inherited = false);
 
 	struct DaysHoursMinutes
 	{
@@ -38,13 +41,13 @@ public:
 		std::string mins;
 	};
 
-	uint32_t GetDuration() const { return m_duration; }
-	uint64_t GetExpireTime() const { return m_expire_time; }
+	uint32_t GetDuration() const { return static_cast<uint32_t>(m_duration.count()); }
+	uint64_t GetExpireTime() const { return std::chrono::system_clock::to_time_t(m_expire_time); }
 	uint32_t GetSecondsRemaining() const;
 	DaysHoursMinutes GetDaysHoursMinutesRemaining() const;
 	const std::string& GetExpeditionName() const { return m_expedition_name; }
 	const std::string& GetEventName() const { return m_event_name; }
-	void SetExpireTime(uint64_t expire_time) { m_expire_time = expire_time; }
+	void SetExpireTime(uint64_t expire_time) { m_expire_time = std::chrono::system_clock::from_time_t(expire_time); }
 	void SetInherited(bool is_inherited) { m_is_inherited = is_inherited; }
 	bool IsExpired() const { return GetSecondsRemaining() == 0; }
 	bool IsInherited() const { return m_is_inherited; }
@@ -55,10 +58,10 @@ public:
 private:
 	std::string m_expedition_name;
 	std::string m_event_name;
-	uint64_t    m_expire_time     = 0;
-	uint32_t    m_duration        = 0;
 	bool        m_is_inherited    = false; // inherited from expedition leader
 	bool        m_is_replay_timer = false;
+	std::chrono::seconds m_duration;
+	std::chrono::time_point<std::chrono::system_clock> m_expire_time;
 };
 
 #endif