diff --git a/macro/beamtime/mcbm2024/README_GeoPar.md b/macro/beamtime/mcbm2024/README_GeoPar.md
index 54ed10a4545cc13d3e9760512fff9d8d4f1f9924..ff01db0495086fac43ca42ad6ce31816fa0823e4 100644
--- a/macro/beamtime/mcbm2024/README_GeoPar.md
+++ b/macro/beamtime/mcbm2024/README_GeoPar.md
@@ -20,6 +20,13 @@
       Rebasing directly from the CLI without caring about the state of the geo and params folders will fail if they are
       in  "mCBM mode" and may lead to a broken local copy \
       => As soon as you start using the `switch_geo_par.sh` script in a Cbmroot copy, rebase it only with this script!!!
+1. Updating/rebasing the mCBM versions of the geometry and parameters folders: just execute the following script
+   ```
+   ./macro/beamtime/mcbm2024/update_geo_par.sh
+   ```
+   => This will bring in the local copy the latest changes from the remote branch in the mCBM fork \
+   => This will also ensure the local copies are compatible with a fast-forward push to the remote branch in the mCBM
+   fork (force-push or any git history changes are not allowed).
 
 # CAVEATS
 
diff --git a/macro/beamtime/mcbm2024/update_geo_par.sh b/macro/beamtime/mcbm2024/update_geo_par.sh
new file mode 100755
index 0000000000000000000000000000000000000000..99c59f95ed4dd71605e8b99738955ea282d5a8a7
--- /dev/null
+++ b/macro/beamtime/mcbm2024/update_geo_par.sh
@@ -0,0 +1,84 @@
+#!/bin/bash
+# Copyright (C) 2024 GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
+# SPDX-License-Identifier: GPL-3.0-only
+# First commited by Pierre-Alain Loizeau
+
+START_DIR=$PWD
+
+# I: pre-checks, this part should be read-only actions in terms of the current files (changes only in .git folders)!
+# I-A: Geometry folder
+# I-A-1) Go to folder
+cd ${VMCWORKDIR}/geometry
+# I-A-2) Check if current version is the Official detached commit or the mCBM repo HEAD
+if [[ 1 -eq $(git status | grep -c "HEAD detached at") ]]; then
+  echo "Geometry folder is in official version, cannot update to get latest mCBM changes, stopping there"
+  exit 2
+fi
+# I-A-3) Check if some local changes are present
+if [[ 0 -ne $(git status --porcelain | wc -l) ]]; then
+  echo "Local changes found in the geometry folder."
+  echo "=> You need to remove them (or commit them if in mCBM mode) before updating"
+  git status --short
+  exit 3
+fi
+# I-B: Parameters folder
+# I-B-1) Go to folder
+cd ${VMCWORKDIR}/parameters
+# I-B-2) Check if current version is the Official detached commit or the mCBM repo HEAD
+if [[ 1 -eq $(git status | grep -c "HEAD detached at") ]]; then
+  echo "Parameters folder is in official version, cannot update to get latest mCBM changes, stopping there"
+  exit 2
+fi
+# I-B-3) Check if some local changes are present
+if [[ 0 -ne $(git status --porcelain | wc -l) ]]; then
+  echo "Local changes found in the parameters folder."
+  echo "=> You need to remove them (or commit them if in mCBM mode) before updating"
+  git status --short
+  exit 3
+fi
+
+# II: Fetch latest changes and rebase the folder on them
+#     => straight-forward if no local commits
+#     => otherwise revert if conflicts found
+# II-A: Geometry folder
+# II-A-1) Go to folder
+cd ${VMCWORKDIR}/geometry
+# II-A-2) Fetch latest changes
+git fetch mcbm
+# II-A-3) Try to rebase, revert if this fails
+if ! git rebase mcbm/mcbm24_master; then
+  echo "Rebasing the geometry folder failed, most probably due to local commits in conflict"
+  echo "Aborting (=reverting) the rebase!!!"
+  git rebase --abort
+  echo "Please rebase by hand in the geometry folder with the following commands:"
+  echo "git rebase mcbm/mcbm24_master  # Will lead to a conflict"
+  echo "git rebase --continue  # After each resolution of problems, for each conflicting commit"
+  echo "git rebase --abort  # If not able to resolve the conflicts"
+  echo "=> If lost, please google \"git rebase resolve conflicts\" or ask other mcbm members"
+  exit 4
+else
+  echo "Now up to date with the mcbm remote version of the geometry folder"
+fi
+# II-A: Parameters folder
+# II-A-1) Go to folder
+cd ${VMCWORKDIR}/parameters
+# II-A-2) Fetch latest changes
+git fetch mcbm
+# II-A-3) Try to rebase, revert if this fails
+if ! git rebase mcbm/mcbm24_master; then
+  echo "Rebasing the parameters folder failed, most probably due to local commits in conflict"
+  echo "Aborting (=reverting) the rebase!!!"
+  git rebase --abort
+  echo "Please rebase by hand in the parameters folder with the following commands:"
+  echo "git rebase mcbm/mcbm24_master  # Will lead to a conflict"
+  echo "git rebase --continue  # After each resolution of problems, for each conflicting commit"
+  echo "git rebase --abort  # If not able to resolve the conflicts"
+  echo "=> If lost, please google \"git rebase resolve conflicts\" or ask other mcbm members"
+  exit 4
+else
+  echo "Now up to date with the mcbm remote version of the parameters folder"
+fi
+
+cd ${START_DIR}
+
+exit 0