diff --git a/src/cryptonote_config.h b/src/cryptonote_config.h
index 4490f86ac..04549e7fc 100644
--- a/src/cryptonote_config.h
+++ b/src/cryptonote_config.h
@@ -40,6 +40,7 @@
 #define CRYPTONOTE_MAX_TX_SIZE                          1000000
 #define CRYPTONOTE_MAX_TX_PER_BLOCK                     0x10000000
 #define CRYPTONOTE_PUBLIC_ADDRESS_TEXTBLOB_VER          0
+#define CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2         288
 #define CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW            60
 #define CURRENT_TRANSACTION_VERSION                     2
 #define CURRENT_BLOCK_MAJOR_VERSION                     7
@@ -189,6 +190,8 @@
 #define HF_VERSION_EXACT_COINBASE               16
 #define HF_VERSION_CLSAG                        16
 #define HF_VERSION_DETERMINISTIC_UNLOCK_TIME    16
+#define HF_VERSION_DYNAMIC_UNLOCK               16
+#define HF_VERSION_FIXED_UNLOCK                 18
 #define HF_VERSION_BULLETPROOF_PLUS             18
 #define HF_VERSION_VIEW_TAGS                    20
 #define HF_VERSION_2021_SCALING                 20
diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 33484ae6e..45d103157 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -1462,7 +1462,18 @@ bool Blockchain::prevalidate_miner_transaction(const block& b, uint64_t height,
     return false;
   }
   MDEBUG("Miner tx hash: " << get_transaction_hash(b.miner_tx));
-  CHECK_AND_ASSERT_MES(b.miner_tx.unlock_time == height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW, false, "coinbase transaction transaction has the wrong unlock time=" << b.miner_tx.unlock_time << ", expected " << height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW);
+  if (hf_version >= HF_VERSION_FIXED_UNLOCK) {
+    CHECK_AND_ASSERT_MES(b.miner_tx.unlock_time == height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2, false, "coinbase transaction transaction has the wrong unlock time=" << b.miner_tx.unlock_time << ", expected " << height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2);
+  } else if (hf_version < HF_VERSION_FIXED_UNLOCK && hf_version >= HF_VERSION_DYNAMIC_UNLOCK) {
+    uint64_t N = m_nettype == MAINNET ? 1337 : 5;
+    crypto::hash blk_id = get_block_id_by_height(height-N);
+    std::string hex_str = epee::string_tools::pod_to_hex(blk_id).substr(0, 3);
+    uint64_t blk_num = std::stol(hex_str,nullptr,16)*2;
+    uint64_t unlock_window = blk_num + 288;
+    CHECK_AND_ASSERT_MES(b.miner_tx.unlock_time == height + unlock_window, false, "coinbase transaction transaction has the wrong unlock time=" << b.miner_tx.unlock_time << ", expected " << height + unlock_window);
+  } else {
+    CHECK_AND_ASSERT_MES(b.miner_tx.unlock_time == height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW, false, "coinbase transaction transaction has the wrong unlock time=" << b.miner_tx.unlock_time << ", expected " << height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW);
+  }
 
   //check outs overflow
   if(!check_outs_overflow(b.miner_tx))
diff --git a/src/cryptonote_core/cryptonote_tx_utils.cpp b/src/cryptonote_core/cryptonote_tx_utils.cpp
index 706ca238e..9b474e02e 100644
--- a/src/cryptonote_core/cryptonote_tx_utils.cpp
+++ b/src/cryptonote_core/cryptonote_tx_utils.cpp
@@ -171,7 +171,7 @@ namespace cryptonote
       tx.version = 1;
 
     //lock
-    tx.unlock_time = height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW;
+    tx.unlock_time = height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2;
     tx.vin.push_back(in);
 
     tx.invalidate_hashes();
diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index fb0fa215c..72cbd9495 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -8331,8 +8331,8 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       gamma.reset(new gamma_picker(rct_offsets));
 
     size_t num_selected_transfers = 0;
-    req.outputs.reserve(selected_transfers.size() * (base_requested_outputs_count + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW));
-    daemon_resp.outs.reserve(selected_transfers.size() * (base_requested_outputs_count + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW));
+    req.outputs.reserve(selected_transfers.size() * (base_requested_outputs_count + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2));
+    daemon_resp.outs.reserve(selected_transfers.size() * (base_requested_outputs_count + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2));
     for(size_t idx: selected_transfers)
     {
       ++num_selected_transfers;
@@ -8340,7 +8340,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       const uint64_t amount = td.is_rct() ? 0 : td.amount();
       std::unordered_set<uint64_t> seen_indices;
       // request more for rct in base recent (locked) coinbases are picked, since they're locked for longer
-      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
+      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2 - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
       size_t start = req.outputs.size();
       bool use_histogram = amount != 0;
 
@@ -8673,7 +8673,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
     for(size_t idx: selected_transfers)
     {
       const transfer_details &td = m_transfers[idx];
-      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
+      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW_V2 - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
       outs.push_back(std::vector<get_outs_entry>());
       outs.back().reserve(fake_outputs_count + 1);
       const rct::key mask = td.is_rct() ? rct::commit(td.amount(), td.m_mask) : rct::zeroCommit(td.amount());