diff --git a/Projects/AthAnalysis/build_externals.sh b/Projects/AthAnalysis/build_externals.sh
index daf7ace342e3997bf513ae839671f4726303a7a0..ff042fd7be4cc1fac07130a188b2600480902481 100755
--- a/Projects/AthAnalysis/build_externals.sh
+++ b/Projects/AthAnalysis/build_externals.sh
@@ -24,7 +24,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
-EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_2"
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_4"
             -DATLAS_GAUDI_TAG="v35r0.002")
 while getopts ":t:b:x:fch" opt; do
     case $opt in
diff --git a/Projects/AthDataQuality/CMakeLists.txt b/Projects/AthDataQuality/CMakeLists.txt
index 0a88450493ede6a79d2766f9f926996887f94a44..df7e365a2238e21983c4ffee13addc9901f5bde1 100644
--- a/Projects/AthDataQuality/CMakeLists.txt
+++ b/Projects/AthDataQuality/CMakeLists.txt
@@ -18,7 +18,7 @@ set( TDAQ-COMMON_ATROOT
 find_package( AtlasCMake REQUIRED )
 
 # Build the project against LCG:
-set( LCG_VERSION_POSTFIX "python3_ATLAS_3"
+set( LCG_VERSION_POSTFIX "python3_ATLAS_4"
    CACHE STRING "Version postfix for the LCG release to use" )
 set( LCG_VERSION_NUMBER 98
    CACHE STRING "Version number for the LCG release to use" )
diff --git a/Projects/AthGeneration/build_externals.sh b/Projects/AthGeneration/build_externals.sh
index bd2ac7f080289cb577f94878332d7bc539783389..a2eb49af201715a8e5de00d1467094285b66a04c 100755
--- a/Projects/AthGeneration/build_externals.sh
+++ b/Projects/AthGeneration/build_externals.sh
@@ -24,7 +24,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
-EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_3"
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_4"
             -DATLAS_GAUDI_TAG="v35r0.002")
 while getopts ":t:b:x:fch" opt; do
     case $opt in
diff --git a/Projects/AthSimulation/build_externals.sh b/Projects/AthSimulation/build_externals.sh
index e7ce96a862f4eaa93610260a301753cda19fbe60..1c2c8b9cfa4957c6c50f7e647bb7b0a5e7397a0f 100755
--- a/Projects/AthSimulation/build_externals.sh
+++ b/Projects/AthSimulation/build_externals.sh
@@ -24,7 +24,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
-EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_3"
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_4"
             -DATLAS_GAUDI_TAG="v35r0.002")
 while getopts ":t:b:x:fch" opt; do
     case $opt in
diff --git a/Projects/Athena/build_externals.sh b/Projects/Athena/build_externals.sh
index 32400efb469dccaf3512dd712b3155cecf49bf7e..9a2a77820ad56558b71b4b3f03e648050908efde 100755
--- a/Projects/Athena/build_externals.sh
+++ b/Projects/Athena/build_externals.sh
@@ -24,7 +24,7 @@ BUILDDIR=""
 BUILDTYPE="RelWithDebInfo"
 FORCE=""
 CI=""
-EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_3"
+EXTRACMAKE=(-DLCG_VERSION_NUMBER=98 -DLCG_VERSION_POSTFIX="python3_ATLAS_4"
             -DATLAS_GAUDI_TAG="v35r0.002")
 while getopts ":t:b:x:fch" opt; do
     case $opt in