diff --git a/conf/File_input/Beidou/gnss-sdr_BDS_B2a_file.conf b/conf/File_input/Beidou/gnss-sdr_BDS_B2a_file.conf
index b64a6f273..a435bece5 100644
--- a/conf/File_input/Beidou/gnss-sdr_BDS_B2a_file.conf
+++ b/conf/File_input/Beidou/gnss-sdr_BDS_B2a_file.conf
@@ -1,7 +1,8 @@
 ; BeiDou B2a (5D) file-input example: 8-bit signed real IF.
 ; Tracks B2a_I (data) at 1 ms primary-code epochs; telemetry combines five
 ; epochs per symbol and applies 64-ary LDPC(96,48) decoding and CRC-24Q.
-; GEO / BDS-2 (PRN 1-18 and 59-63) are not assigned B2a channels.
+; GEO PRNs 1-5 and 59-63 are excluded: GEO B2a decoding/PVT is not supported.
+; The 2026 reassignment places BDS-3 IGSO/MEO satellites at PRNs 6-8 and 11-14.
 ;
 ; PVT policy (B2a-only SPP):
 ;   - RTKLIB slot 0 holds 5D; satwavelen BDS frq2 stays B3, lam[0] is c/FREQ5.
diff --git a/src/core/receiver/gnss_flowgraph.cc b/src/core/receiver/gnss_flowgraph.cc
index 356f31a58..9a9f3a760 100644
--- a/src/core/receiver/gnss_flowgraph.cc
+++ b/src/core/receiver/gnss_flowgraph.cc
@@ -2517,16 +2517,17 @@ void GNSSFlowgraph::set_signals_list()
                         {
                             if (signal_str == "1D")
                                 {
-                                    if ((prn >= 1U && prn <= 5U) || (prn >= 59U && prn <= 63U))
+                                    // The 2026-03-20 CSNO allocation adds B1C on GEO PRNs 1-4.
+                                    if (prn == 5U || (prn >= 59U && prn <= 63U))
                                         {
-                                            continue;  // GEO satellites do not broadcast B1C (ICD section 3.1)
+                                            continue;
                                         }
                                 }
                             if (signal_str == "5D")
                                 {
                                     if ((prn >= 1U && prn <= 5U) || (prn >= 59U && prn <= 63U))
                                         {
-                                            continue;  // GEO satellites do not broadcast B2a RNSS (ICD §2)
+                                            continue;  // GEO B2a decoding/PVT is not supported.
                                         }
                                 }
                             if (signal_str == "J5" && prn > QZSS_L5_MAX_PRN)
diff --git a/src/core/system_parameters/gnss_satellite.cc b/src/core/system_parameters/gnss_satellite.cc
index 5894c65f5..0498d8eaf 100644
--- a/src/core/system_parameters/gnss_satellite.cc
+++ b/src/core/system_parameters/gnss_satellite.cc
@@ -611,148 +611,125 @@ std::string Gnss_Satellite::what_block(const std::string& system_, uint32_t PRN_
         }
     if (system_ == "Beidou")
         {
-            // Check https://en.wikipedia.org/wiki/List_of_BeiDou_satellites
+            // Post-upgrade allocation announced by CSNO on 2026-03-20:
+            // http://www.beidou.gov.cn/yw/xwzx/202603/t20260320_29266.html
+            // These display labels describe that allocation, not historical recordings.
+            // Signal processing must not infer orbit type or signal availability from them.
             switch (PRN_)
                 {
                 case 1:
-                    block_ = std::string("BeiDou-2 GEO01*");  // GEO 140.0°E; launched 2010/01/16 (Retired)
+                    block_ = std::string("BeiDou-3 GEO04");  // Former PRN 62; GEO 140.0 E
                     break;
                 case 2:
-                    block_ = std::string("BeiDou-2 GEO06");  // GEO 80°E; launched 2012/10/25
+                    block_ = std::string("BeiDou-3 GEO02");  // Former PRN 60; GEO 80 E
                     break;
                 case 3:
-                    block_ = std::string("BeiDou-2 GEO07");  // GEO 110.5°E; launched 2016/06/12
+                    block_ = std::string("BeiDou-3 GEO03");  // Former PRN 61; GEO 110.5 E
                     break;
                 case 4:
-                    block_ = std::string("BeiDou-2 GEO04");  // GEO 160.0°E; launched 2010/10/31
-                    break;
-                case 5:
-                    block_ = std::string("BeiDou-2 GEO05");  // GEO 58.75°E; launched 2012/02/24
+                    block_ = std::string("BeiDou-3 GEO01");  // Former PRN 59; GEO 160 E
                     break;
                 case 6:
-                    block_ = std::string("BeiDou-2 IGSO01");  // 55° inclination IGSO 118°E; launched 2010/07/31
+                    block_ = std::string("BeiDou-3 IGSO01");  // Former PRN 38
                     break;
                 case 7:
-                    block_ = std::string("BeiDou-2 IGSO02");  // 55° inclination IGSO 118°E; launched 2010/12/17
+                    block_ = std::string("BeiDou-3 IGSO02");  // Former PRN 39
                     break;
                 case 8:
-                    block_ = std::string("BeiDou-2 IGSO03");  // 55° inclination IGSO 118°E; launched 2011/04/09
+                    block_ = std::string("BeiDou-3 IGSO03");  // Former PRN 40
                     break;
                 case 9:
-                    block_ = std::string("BeiDou-2 IGSO04");  // 55° inclination IGSO 95°E; launched 2011/07/27
+                    block_ = std::string("BeiDou-2 IGSO06");  // Former PRN 13
                     break;
                 case 10:
-                    block_ = std::string("BeiDou-2 IGSO05");  // 55° inclination IGSO 118°E; launched 2011/12/01
+                    block_ = std::string("BeiDou-2 IGSO07");  // Former PRN 16
                     break;
                 case 11:
-                    block_ = std::string("BeiDou-2 MEO03*");  // Slot A07; launched 2012/04/29 (Retired)
+                    block_ = std::string("BeiDou-3 MEO25");  // Former PRN 47
                     break;
                 case 12:
-                    block_ = std::string("BeiDou-2 MEO04*");  // Slot A08; launched 2012/04/29 (Retired)
+                    block_ = std::string("BeiDou-3 MEO26");  // Former PRN 48
                     break;
                 case 13:
-                    block_ = std::string("BeiDou-2 IGSO06");  // launched 2016/03/30
+                    block_ = std::string("BeiDou-3 MEO27");  // Former PRN 49; PRN 13 now identifies a MEO satellite
                     break;
                 case 14:
-                    block_ = std::string("BeiDou-2 MEO06*");  // launched 2012/09/19 (Retired)
-                    break;
-                case 16:
-                    block_ = std::string("BeiDou-2 IGSO07");  // launched 2018/07/10
-                    break;
-                case 18:
-                    block_ = std::string("BeiDou-3 GEOG8");  // launched 2019/05/17
+                    block_ = std::string("BeiDou-3 MEO28");  // Former PRN 50
                     break;
                 case 19:
-                    block_ = std::string("BeiDou-3 MEO01");  // Slot B07; launched 2017/11/05
+                    block_ = std::string("BeiDou-3 MEO01");
                     break;
                 case 20:
-                    block_ = std::string("BeiDou-3 MEO02");  // Slot B05; launched 2017/11/05
+                    block_ = std::string("BeiDou-3 MEO02");
                     break;
                 case 21:
-                    block_ = std::string("BeiDou-3 MEO03");  // Slot B0?; launched 2018/02/12
+                    block_ = std::string("BeiDou-3 MEO03");
                     break;
                 case 22:
-                    block_ = std::string("BeiDou-3 MEO04");  // Slot B06; launched 2018/02/12
+                    block_ = std::string("BeiDou-3 MEO04");
                     break;
                 case 23:
-                    block_ = std::string("BeiDou-3 MEO05");  // Slot C07; launched 2018/07/29
+                    block_ = std::string("BeiDou-3 MEO05");
                     break;
                 case 24:
-                    block_ = std::string("BeiDou-3 MEO06");  // Slot C01; launched 2018/07/29
+                    block_ = std::string("BeiDou-3 MEO06");
                     break;
                 case 25:
-                    block_ = std::string("BeiDou-3 MEO11");  // Slot C08; launched 2018/08/24
+                    block_ = std::string("BeiDou-3 MEO11");
                     break;
                 case 26:
-                    block_ = std::string("BeiDou-3 MEO12");  // Slot C02; launched 2018/08/24
+                    block_ = std::string("BeiDou-3 MEO12");
                     break;
                 case 27:
-                    block_ = std::string("BeiDou-3 3M3");  // Slot A04; launched 2018/01/11
+                    block_ = std::string("BeiDou-3 MEO07");
                     break;
                 case 28:
-                    block_ = std::string("BeiDou-3 3M4");  // Slot A05; launched 2018/01/11
+                    block_ = std::string("BeiDou-3 MEO08");
                     break;
                 case 29:
-                    block_ = std::string("BeiDou-3 3M7");  // Slot A02; launched 2018/03/29
+                    block_ = std::string("BeiDou-3 MEO09");
                     break;
                 case 30:
-                    block_ = std::string("BeiDou-3 3M8");  // Slot A03; launched 2018/03/29
+                    block_ = std::string("BeiDou-3 MEO10");
+                    break;
+                case 31:
+                    block_ = std::string("BeiDou-3 MEO22");  // Former PRN 44
                     break;
                 case 32:
-                    block_ = std::string("BeiDou-3 MEO13");  // Slot B01; launched 2018/09/19
+                    block_ = std::string("BeiDou-3 MEO13");
                     break;
                 case 33:
-                    block_ = std::string("BeiDou-3 MEO14");  // Slot B03; launched 2018/09/19
+                    block_ = std::string("BeiDou-3 MEO14");
                     break;
                 case 34:
-                    block_ = std::string("BeiDou-3 MEO15");  // Slot B03; launched 2018/10/15
+                    block_ = std::string("BeiDou-3 MEO15");
                     break;
                 case 35:
-                    block_ = std::string("BeiDou-3 MEO16");  // Slot B03; launched 2018/10/15
+                    block_ = std::string("BeiDou-3 MEO16");
                     break;
                 case 36:
-                    block_ = std::string("BeiDou-3 MEO17");  // Slot B03; launched 2018/11/18
+                    block_ = std::string("BeiDou-3 MEO17");
                     break;
                 case 37:
-                    block_ = std::string("BeiDou-3 MEO18");  // Slot B03; launched 2018/11/18
+                    block_ = std::string("BeiDou-3 MEO18");
                     break;
                 case 38:
-                    block_ = std::string("BeiDou-3 IGSOI1");  // launched 2019/04/20
+                    block_ = std::string("BeiDou-3 MEO21");  // Former PRN 43
                     break;
                 case 39:
-                    block_ = std::string("BeiDou-3 IGSOI2");  // launched 2019/04/20
+                    block_ = std::string("BeiDou-3 MEO23");  // Former PRN 45
                     break;
                 case 40:
-                    block_ = std::string("BeiDou-3 IGSOI3");  // launched 2019/11/04
+                    block_ = std::string("BeiDou-3 MEO24");  // Former PRN 46
                     break;
                 case 41:
-                    block_ = std::string("BeiDou-3 MEO19");  // Slot B02, launched 2019/12/16
+                    block_ = std::string("BeiDou-3 MEO19");
                     break;
                 case 42:
-                    block_ = std::string("BeiDou-3 MEO20");  // Slot B04, launched 2019/12/16
-                    break;
-                case 43:
-                    block_ = std::string("BeiDou-3 MEO21");  // Slot A06, launched 2019/11/23
-                    break;
-                case 44:
-                    block_ = std::string("BeiDou-3 MEO22");  // Slot A08, launched 2019/11/23
-                    break;
-                case 45:
-                    block_ = std::string("BeiDou-3 MEO23");  // Slot C03, launched 2019/09/22
-                    break;
-                case 46:
-                    block_ = std::string("BeiDou-3 MEO24");  // Slot C05, launched 2019/09/22
-                    break;
-                case 59:
-                    block_ = std::string("BeiDou-3 GEOG1");  // launched 2018/11/01
-                    break;
-                case 60:
-                    block_ = std::string("BeiDou-3 GEOG2");  // launched 2020/03/20
-                    break;
-                case 61:
-                    block_ = std::string("BeiDou-3 GEOG3");  // launched 2020/06/2023
+                    block_ = std::string("BeiDou-3 MEO20");
                     break;
                 default:
+                    // PRNs 5 and 15-18 are reserved; 43-63 are not in this allocation.
                     block_ = std::string("Unknown");
                 }
         }