diff --git a/src/fragment_store/message_fragment_store.cpp b/src/fragment_store/message_fragment_store.cpp
index b4b4186e..d53f4415 100644
--- a/src/fragment_store/message_fragment_store.cpp
+++ b/src/fragment_store/message_fragment_store.cpp
@@ -22,8 +22,6 @@ namespace Message::Components {
 	// ctx
 	struct OpenFragments {
 		struct OpenFrag final {
-			uint64_t ts_begin {0};
-			uint64_t ts_end {0};
 			std::vector<uint8_t> uid;
 		};
 		// only contains fragments with <1024 messages and <28h tsrage
@@ -93,9 +91,15 @@ void MessageFragmentStore::handleMessage(const Message3Handle& m) {
 		std::vector<uint8_t> fragment_uid;
 
 		// first search for fragment where the ts falls into the range
-		for (const auto& [ts_begin, ts_end, fid] : fuid_open) {
-			if (ts_begin <= msg_ts && ts_end >= msg_ts) {
-				fragment_uid = fid;
+		for (const auto& fuid : fuid_open) {
+			auto fh = _fs.fragmentHandle(_fs.getFragmentByID(fuid.uid));
+			assert(static_cast<bool>(fh));
+
+			// assuming ts range exists
+			auto& fts_comp = fh.get<FragComp::MessagesTSRange>();
+
+			if (fts_comp.begin <= msg_ts && fts_comp.end >= msg_ts) {
+				fragment_uid = fuid.uid;
 				// TODO: check conditions for open here
 				// TODO: mark msg (and frag?) dirty
 			}
@@ -103,39 +107,37 @@ void MessageFragmentStore::handleMessage(const Message3Handle& m) {
 
 		// if it did not fit into an existing fragment, we next look for fragments that could be extended
 		if (fragment_uid.empty()) {
-			for (auto& [ts_begin, ts_end, fid] : fuid_open) {
-				const int64_t frag_range = int64_t(ts_end) - int64_t(ts_begin);
+			for (const auto& fuid : fuid_open) {
+				auto fh = _fs.fragmentHandle(_fs.getFragmentByID(fuid.uid));
+				assert(static_cast<bool>(fh));
+
+				// assuming ts range exists
+				auto& fts_comp = fh.get<FragComp::MessagesTSRange>();
+
+				const int64_t frag_range = int64_t(fts_comp.end) - int64_t(fts_comp.begin);
 				constexpr static int64_t max_frag_ts_extent {1000*60*60};
 				//constexpr static int64_t max_frag_ts_extent {1000*60*3}; // 3min for testing
 				const int64_t possible_extention = max_frag_ts_extent - frag_range;
 
 				// which direction
-				if ((ts_begin - possible_extention) <= msg_ts && ts_begin > msg_ts) {
-					fragment_uid = fid;
-					auto fh = _fs.fragmentHandle(_fs.getFragmentByID(fid));
-					assert(static_cast<bool>(fh));
+				if ((fts_comp.begin - possible_extention) <= msg_ts && fts_comp.begin > msg_ts) {
+					fragment_uid = fuid.uid;
 
-					std::cout << "MFS: extended begin from " << ts_begin << " to " << msg_ts << "\n";
+					std::cout << "MFS: extended begin from " << fts_comp.begin << " to " << msg_ts << "\n";
 
 					// assuming ts range exists
-					auto& fts_comp = fh.get<FragComp::MessagesTSRange>();
 					fts_comp.begin = msg_ts; // extend into the past
-					ts_begin = msg_ts;
 
 
 					// TODO: check conditions for open here
 					// TODO: mark msg (and frag?) dirty
-				} else if ((ts_end + possible_extention) >= msg_ts && ts_end < msg_ts) {
-					fragment_uid = fid;
-					auto fh = _fs.fragmentHandle(_fs.getFragmentByID(fid));
-					assert(static_cast<bool>(fh));
+				} else if ((fts_comp.end + possible_extention) >= msg_ts && fts_comp.end < msg_ts) {
+					fragment_uid = fuid.uid;
 
-					std::cout << "MFS: extended end from " << ts_end << " to " << msg_ts << "\n";
+					std::cout << "MFS: extended end from " << fts_comp.end << " to " << msg_ts << "\n";
 
 					// assuming ts range exists
-					auto& fts_comp = fh.get<FragComp::MessagesTSRange>();
 					fts_comp.end = msg_ts; // extend into the future
-					ts_end = msg_ts;
 
 					// TODO: check conditions for open here
 					// TODO: mark msg (and frag?) dirty
@@ -157,7 +159,7 @@ void MessageFragmentStore::handleMessage(const Message3Handle& m) {
 			fh.emplace_or_replace<FragComp::Ephemeral::MetaCompressionType>().comp = Compression::ZSTD;
 			fh.emplace_or_replace<FragComp::DataCompressionType>().comp = Compression::ZSTD;
 
-			auto& new_ts_range = fh.emplace<FragComp::MessagesTSRange>();
+			auto& new_ts_range = fh.emplace_or_replace<FragComp::MessagesTSRange>();
 			new_ts_range.begin = msg_ts;
 			new_ts_range.end = msg_ts;
 
@@ -170,7 +172,7 @@ void MessageFragmentStore::handleMessage(const Message3Handle& m) {
 				}
 			}
 
-			fuid_open.emplace_back(Message::Components::OpenFragments::OpenFrag{msg_ts, msg_ts, fragment_uid});
+			fuid_open.emplace_back(Message::Components::OpenFragments::OpenFrag{fragment_uid});
 
 			std::cout << "MFS: created new fragment " << bin2hex(fragment_uid) << "\n";
 
@@ -306,6 +308,10 @@ float MessageFragmentStore::tick(float time_delta) {
 		const auto fid = _fs.getFragmentByID(_fuid_save_queue.front().id);
 		auto* reg = _fuid_save_queue.front().reg;
 		assert(reg != nullptr);
+
+		auto fh = _fs.fragmentHandle(fid);
+		auto& ftsrange = fh.get_or_emplace<FragComp::MessagesTSRange>(Message::getTimeMS(), Message::getTimeMS());
+
 		auto j = nlohmann::json::array();
 
 		// TODO: does every message have ts?
@@ -327,6 +333,15 @@ float MessageFragmentStore::tick(float time_delta) {
 				continue; // not ours
 			}
 
+			{ // potentially adjust tsrange (some external processes can change timestamps)
+				const auto msg_ts = msg_view.get<Message::Components::Timestamp>(m).ts;
+				if (ftsrange.begin > msg_ts) {
+					ftsrange.begin = msg_ts;
+				} else if (ftsrange.end < msg_ts) {
+					ftsrange.end = msg_ts;
+				}
+			}
+
 			auto& j_entry = j.emplace_back(nlohmann::json::object());
 
 			for (const auto& [type_id, storage] : reg->storage()) {