diff --git a/pocket/pocket.lua b/pocket/pocket.lua
index 007f01d..6f876ea 100644
--- a/pocket/pocket.lua
+++ b/pocket/pocket.lua
@@ -314,7 +314,7 @@ function pocket.comms(version, modem, pkt_channel, svr_channel, crd_channel, ran
                     elseif not self.api.linked then
                         log.debug("discarding coordinator non-link SCADA_MGMT packet before linked")
                     else
-                        log.debug("discarding SCADA_MGMT from different coordinator (src_addr " .. src_addr .. " ≠ " .. self.api.addr .. ")")
+                        log.debug("discarding non-link SCADA_MGMT packet from different coordinator (src_addr " .. src_addr .. " ≠ " .. self.api.addr .. ")")
                     end
                 else
                     log.debug("illegal packet type " .. protocol .. " from coordinator", true)
@@ -405,7 +405,7 @@ function pocket.comms(version, modem, pkt_channel, svr_channel, crd_channel, ran
                     elseif not self.sv.linked then
                         log.debug("discarding supervisor non-link SCADA_MGMT packet before linked")
                     else
-                        log.debug("discarding SCADA_MGMT from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv.addr .. ")")
+                        log.debug("discarding non-link SCADA_MGMT from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv.addr .. ")")
                     end
                 else
                     log.debug("illegal packet type " .. protocol .. " from supervisor", true)
diff --git a/pocket/startup.lua b/pocket/startup.lua
index c1dc37b..14317fd 100644
--- a/pocket/startup.lua
+++ b/pocket/startup.lua
@@ -17,7 +17,7 @@ local coreio   = require("pocket.coreio")
 local pocket   = require("pocket.pocket")
 local renderer = require("pocket.renderer")
 
-local POCKET_VERSION = "alpha-v0.4.2"
+local POCKET_VERSION = "alpha-v0.4.3"
 
 local println = util.println
 local println_ts = util.println_ts
diff --git a/reactor-plc/plc.lua b/reactor-plc/plc.lua
index efe6aaa..4cd34ad 100644
--- a/reactor-plc/plc.lua
+++ b/reactor-plc/plc.lua
@@ -938,7 +938,7 @@ function plc.comms(id, version, modem, plc_channel, svr_channel, range, reactor,
                 elseif not self.linked then
                     log.debug("discarding RPLC packet before linked")
                 else
-                    log.debug("discarding RPLC from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv_addr .. "sv_addr)")
+                    log.debug("discarding RPLC packet from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv_addr .. ")")
                 end
             elseif protocol == PROTOCOL.SCADA_MGMT then
                 ---@cast packet mgmt_frame
@@ -1057,8 +1057,10 @@ function plc.comms(id, version, modem, plc_channel, svr_channel, range, reactor,
                     else
                         log.debug("SCADA_MGMT establish packet length mismatch")
                     end
-                else
+                elseif not self.linked then
                     log.debug("discarding non-link SCADA_MGMT packet before linked")
+                else
+                    log.debug("discarding non-link SCADA_MGMT packet from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv_addr .. ")")
                 end
             else
                 -- should be unreachable assuming packet is from parse_packet()
diff --git a/reactor-plc/startup.lua b/reactor-plc/startup.lua
index 5d0234f..e04238d 100644
--- a/reactor-plc/startup.lua
+++ b/reactor-plc/startup.lua
@@ -18,7 +18,7 @@ local plc      = require("reactor-plc.plc")
 local renderer = require("reactor-plc.renderer")
 local threads  = require("reactor-plc.threads")
 
-local R_PLC_VERSION = "v1.4.3"
+local R_PLC_VERSION = "v1.4.4"
 
 local println = util.println
 local println_ts = util.println_ts
diff --git a/rtu/rtu.lua b/rtu/rtu.lua
index a1cc9dc..c97d918 100644
--- a/rtu/rtu.lua
+++ b/rtu/rtu.lua
@@ -354,7 +354,7 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
             -- handle packet
             if protocol == PROTOCOL.MODBUS_TCP then
                 ---@cast packet modbus_frame
-                if rtu_state.linked then
+                if rtu_state.linked and (src_addr == self.sv_addr) then
                     local return_code   ---@type boolean
                     local reply         ---@type modbus_packet
 
@@ -394,8 +394,10 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
                     end
 
                     public.send_modbus(reply)
-                else
+                elseif not rtu_state.linked then
                     log.debug("discarding MODBUS packet before linked")
+                else
+                    log.debug("discarding MODBUS packet from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv_addr .. ")")
                 end
             elseif protocol == PROTOCOL.SCADA_MGMT then
                 ---@cast packet mgmt_frame
@@ -434,7 +436,7 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
                     else
                         log.debug("SCADA_MGMT establish packet length mismatch")
                     end
-                elseif rtu_state.linked then
+                elseif rtu_state.linked and (src_addr == self.sv_addr) then
                     if packet.type == SCADA_MGMT_TYPE.KEEP_ALIVE then
                         -- keep alive request received, echo back
                         if packet.length == 1 and type(packet.data[1]) == "number" then
@@ -464,8 +466,10 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
                         -- not supported
                         log.debug("received unsupported SCADA_MGMT message type " .. packet.type)
                     end
-                else
+                elseif not rtu_state.linked then
                     log.debug("discarding non-link SCADA_MGMT packet before linked")
+                else
+                    log.debug("discarding non-link SCADA_MGMT packet from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv_addr .. ")")
                 end
             else
                 -- should be unreachable assuming packet is from parse_packet()
diff --git a/rtu/startup.lua b/rtu/startup.lua
index 58970f7..0bd3c35 100644
--- a/rtu/startup.lua
+++ b/rtu/startup.lua
@@ -28,7 +28,7 @@ local sna_rtu      = require("rtu.dev.sna_rtu")
 local sps_rtu      = require("rtu.dev.sps_rtu")
 local turbinev_rtu = require("rtu.dev.turbinev_rtu")
 
-local RTU_VERSION = "v1.3.3"
+local RTU_VERSION = "v1.3.4"
 
 local RTU_UNIT_TYPE = types.RTU_UNIT_TYPE
 local RTU_UNIT_HW_STATE = databus.RTU_UNIT_HW_STATE