diff --git a/data/common/common.yaml b/data/common/common.yaml
--- a/data/common/common.yaml
+++ b/data/common/common.yaml
@@ -2554,7 +2554,17 @@
 swh::deploy::worker::loader_opam::user: swhworker
 swh::deploy::worker::loader_opam::group: swhworker
 swh::deploy::worker::opam::root_directory: /tmp/opam/
+
+# Keep opam.ocaml.org entry as the first one which is the default repository
+swh::deploy::worker::opam::default_instance::name: opam.ocaml.org
+swh::deploy::worker::opam::default_instance::url: https://opam.ocaml.org
+
 swh::deploy::worker::opam::instances:
+  coq.inria.fr: https://coq.inria.fr/opam/released
+  ocamlbench-repo: https://github.com/OCamlPro/ocamlbench-repo.git
+
+# deprecated
+swh::deploy::worker::opam::deprecated::instances:
   opam.ocaml.org: https://opam.ocaml.org
   coq.inria.fr: https://coq.inria.fr/opam/released
   ocamlbench-repo: https://github.com/OCamlPro/ocamlbench-repo.git
diff --git a/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp b/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp
--- a/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp
+++ b/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp
@@ -21,12 +21,23 @@
     ],
   }
 
-  $opam_instances = lookup('swh::deploy::worker::opam::instances')
-  $template_path = "profile/swh/deploy/loader_opam"
-
   $opam_root = lookup('swh::deploy::worker::opam::root_directory')
   $opam_manage_shared_state = "opam-manage-shared-state"
   $opam_manage_state_script = "/usr/local/bin/${opam_manage_shared_state}.sh"
+
+  # Install more robust opam root folder maintenance tooling
+  $default_instance_name = lookup('swh::deploy::worker::opam::default_instance::name')
+  $default_instance_url = lookup('swh::deploy::worker::opam::default_instance::url')
+  $other_instances = lookup('swh::deploy::worker::opam::instances')
+
+  $template_path = "profile/swh/deploy/loader_opam"
+
+  # Templates uses variables
+  # - $user
+  # - $group
+  # - $default_instance_name
+  # - $default_instance_url
+  # - $other_instances
   file {$opam_manage_state_script:
     ensure => 'file',
     owner  => $user,
@@ -35,25 +46,39 @@
     content => template("${template_path}/${opam_manage_shared_state}.sh.erb"),
   }
 
+  # Templates uses variables
+  # - $user
+  # - $group
+  # - $runparts_systemd_directory
+  # - $opam_manage_service_name
+  # - $opam_manage_state_script
+
+  ::systemd::timer { "${opam_manage_shared_state}.timer":
+    timer_content    => template("${template_path}/${opam_manage_shared_state}.timer.erb"),
+    service_content  => template("${template_path}/${opam_manage_shared_state}.service.erb"),
+    enable           => true,
+    require          => [
+      Package[$packages],
+      File[$runparts_systemd_directory],
+    ],
+  }
+
+  ###################################################################
+  # Clean up old opam root maintenance tooling (to drop once applied)
+  ###################################################################
+
+  $opam_instances = lookup('swh::deploy::worker::opam::deprecated::instances')
+
   each ( $opam_instances ) | $instance, $instance_url | {
-    $opam_manage_service_name = "${$opam_manage_shared_state}-${instance}"
-    $opam_manage_shared_state_timer_name = "${opam_manage_service_name}.timer"
-
-    # Templates uses variables
-    #  - $user
-    #  - $group
-    #  - $opam_root
-    #  - $opam_manage_service_name
-    #  - $command
-
-    ::systemd::timer { $opam_manage_shared_state_timer_name:
-      timer_content    => template("${template_path}/${opam_manage_shared_state}.timer.erb"),
-      service_content  => template("${template_path}/${opam_manage_shared_state}.service.erb"),
-      enable           => true,
-      require          => [
-        Package[$packages],
-        File[$opam_manage_state_script],
-      ],
+    $opam_manage_service_name = "${opam_manage_shared_state}-${instance}"
+    $opam_manage_service_path = "${default_systemd_path}/${$opam_manage_service_name}.service"
+    $opam_manage_shared_state_timer_name = $opam_manage_service_name
+    $opam_manage_shared_state_timer_path = "${default_systemd_path}/${opam_manage_shared_state_timer_name}.timer"
+
+    # deactivate timer
+    ::systemd::timer { "${opam_manage_shared_state_timer_name}.timer":
+      enable => false,
+      ensure => absent,
     }
   }
 
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb
--- a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb
+++ b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb
@@ -3,7 +3,7 @@
 # Changes will be overwritten
 
 [Unit]
-Description=Software Heritage Manage OPAM shared state (<%= @instance %>)
+Description=Software Heritage Manage OPAM shared state
 Requires=network.target
 After=network.target
 
@@ -11,7 +11,7 @@
 User=<%= @user %>
 Group=<%= @group %>
 Type=simple
-ExecStart=/usr/local/bin/opam-manage-shared-state.sh <%= @instance %> <%= @instance_url %>
+ExecStart=<%= @opam_manage_state_script %>
 
 [Install]
 WantedBy=multi-user.target
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.sh.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.sh.erb
--- a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.sh.erb
+++ b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.sh.erb
@@ -3,20 +3,49 @@
 # Managed by puppet class profile::swh::deploy::worker::loader_opam
 # Changes will be overwritten
 
-CMD=/usr/bin/opam
+# This script is in charge of bootstraping the opam root folder with the default opam
+# repository.
+
+set -e
+
 ROOT_DIR=<%= @opam_root %>
-DEFAULT_INSTANCE="opam.ocaml.org"
-INSTANCE=$1
-INSTANCE_URL=$2
-
-if [ $INSTANCE = $DEFAULT_INSTANCE ]; then
-  # Opam instance is considered the main instance so we must initialize the repository
-  # if not present, otherwise we update it
-  ( $CMD repo --all --root $ROOT_DIR | grep $INSTANCE_URL && $CMD update --root $ROOT_DIR ) \
-      || $CMD init --reinit --bare --no-setup --root $ROOT_DIR $INSTANCE $INSTANCE_URL
-else
-  # Other instances, if present should be updated. If not present, they should be added
-  # to the main root_dir as extra instances
-  ( $CMD repo --all --root $ROOT_DIR | grep $INSTANCE_URL && $CMD update --root $ROOT_DIR ) \
-    || $CMD repository add --root $ROOT_DIR $INSTANCE $INSTANCE_URL
-fi
+CMD=/usr/bin/opam
+
+function init_or_update_opam_root () {
+  # Ensure opam root directory exists and references the main opam repository as default
+  # instance. If not, create it from scratch. If properly configured, update the opam
+  # repository
+
+  instance_name=$1
+  instance_url=$2
+
+  if $CMD repo --all --root $ROOT_DIR | grep -qx $instance_url; then
+    $CMD update --root $ROOT_DIR
+  else
+    $CMD init --reinit --bare --no-setup --root $ROOT_DIR $instance_name $instance_url
+  fi
+}
+
+function init_or_update_opam_instance () {
+  # Ensure opam root directory exists and references the main opam repository as default
+  # instance. If not, create it from scratch. If properly configured, update the opam
+  # repository.
+
+  # Note that This assumes that the function init_or_update_opam_root already got called
+  # prior to calling this one.
+
+  instance_name=$1
+  instance_url=$2
+
+  if $CMD repo --all --root $ROOT_DIR | grep -qx $instance_url; then
+    $CMD update --root $ROOT_DIR
+  else
+    $CMD repository add --root $ROOT_DIR --all-switches $instance_name $instance_url
+  fi
+}
+
+init_or_update_opam_root <%= @default_instance_name %> <%= @default_instance_url %>
+
+<% @other_instances.each do |instance_name, instance_url| %>
+init_or_update_opam_instance <%= instance_name %> <%= instance_url %>
+<% end %>
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb
--- a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb
+++ b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb
@@ -3,9 +3,12 @@
 
 [Timer]
 OnCalendar=daily
-AccuracySec=4h
 Persistent=true
+# every ~4h
+AccuracySec=4h
+RandomizedDelaySec=1200
+FixedRandomDelay=true
 Unit=<%= @opam_manage_service_name %>.service
 
 [Unit]
-Description=Software Heritage Manage OPAM shared state (<%= @instance %>) timer
+Description=Software Heritage Manage OPAM shared state timer