diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2249490..e2e5913 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,7 +12,7 @@ on:
 # A workflow run is made up of one or more jobs that can run sequentially or in parallel
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v2
         with:
@@ -28,7 +28,7 @@ jobs:
       - name: Run tests
         run: test/test.sh
   coverage:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v2
         with:
diff --git a/backup.sh b/backup.sh
index af4ad58..84a90e1 100755
--- a/backup.sh
+++ b/backup.sh
@@ -24,6 +24,7 @@ RESTIC_HOSTNAME="" # Leave empty to use system hostname
 LOCK_FILE="" # Optional lock file to acquire to ensure two backups don't run at once
 LOCK_FILE_TIMEOUT="" # Optional lock file wait timeout (in seconds)
 WINDOW_MANAGER="screen" # Choices: screen, tmux, RCON
+SAVE_ALL_WAIT_SECONDS="" # Delay in seconds after save-all flush (default: 5, 0 if rcon)
 
 # Other Variables (do not modify)
 DATE_FORMAT="%F_%H-%M-%S"
@@ -41,7 +42,7 @@ debug-log () {
   fi
 }
 
-while getopts 'a:cd:e:f:hH:i:l:m:o:p:qr:s:t:u:vw:x' FLAG; do
+while getopts 'a:cd:e:f:hH:i:l:m:o:p:qr:s:t:u:vw:xz:' FLAG; do
   case $FLAG in
     a) COMPRESSION_ALGORITHM=$OPTARG ;;
     c) ENABLE_CHAT_MESSAGES=true ;;
@@ -69,6 +70,7 @@ while getopts 'a:cd:e:f:hH:i:l:m:o:p:qr:s:t:u:vw:x' FLAG; do
        echo "-u    Lock file timeout seconds (empty = unlimited)"
        echo "-v    Verbose mode"
        echo "-w    Window manager: screen (default), tmux, RCON"
+       echo "-z    Delay in seconds after save-all flush (default: 5, 0 if rcon)"
        exit 0
        ;;
     H) RESTIC_HOSTNAME=$OPTARG ;;
@@ -84,6 +86,7 @@ while getopts 'a:cd:e:f:hH:i:l:m:o:p:qr:s:t:u:vw:x' FLAG; do
     u) LOCK_FILE_TIMEOUT=$OPTARG ;;
     v) DEBUG=true ;;
     w) WINDOW_MANAGER=$OPTARG ;;
+    z) SAVE_ALL_WAIT_SECONDS=$OPTARG ;;
     *) log-fatal "Invalid option -$FLAG"; exit 1 ;;
   esac
 done
@@ -290,6 +293,25 @@ message-players-color () {
     execute-command "tellraw @a [\"\",{\"text\":\"[$PREFIX] \",\"color\":\"gray\",\"italic\":true},{\"text\":\"$MESSAGE\",\"color\":\"$COLOR\",\"italic\":true,\"hoverEvent\":{\"action\":\"show_text\",\"value\":{\"text\":\"\",\"extra\":[{\"text\":\"$HOVER_MESSAGE\"}]}}}]"
   fi
 }
+save-all-flush-delay-seconds () {
+  if [[ -n "$SAVE_ALL_WAIT_SECONDS" ]]; then
+    echo "$SAVE_ALL_WAIT_SECONDS"
+    return
+  fi
+
+  case "$WINDOW_MANAGER" in
+    # RCON already waits for response
+    "RCON"|"rcon"|"docker-rcon") echo "0"
+      ;;
+    *) echo "5" # default value for all other cases
+      ;;
+  esac
+}
+execute-save-all-flush () {
+  execute-command "save-all" # for versions <1.16
+  execute-command "save-all flush"
+  sleep "$(save-all-flush-delay-seconds)"
+}
 
 # Parse file timestamp to one readable by "date" 
 parse-file-timestamp () {
@@ -489,9 +511,12 @@ do-backup () {
   # Notify players of start
   message-players "Starting backup..." "$ARCHIVE_PATH"
 
-  # Disable world autosaving
+  # Disable world autosaving, still allows save-all
   execute-command "save-off"
 
+  # Trigger save now to get most up-to-date data
+  execute-save-all-flush
+
   # Backup world
   START_TIME=$(date +"%s")
 
diff --git a/test/data/test-chat-messages.txt b/test/data/test-chat-messages.txt
index 65aaeb4..75615f1 100644
--- a/test/data/test-chat-messages.txt
+++ b/test/data/test-chat-messages.txt
@@ -1,5 +1,7 @@
 tellraw @a ["",{"text":"[Backup] ","color":"gray","italic":true},{"text":"Starting backup...","color":"gray","italic":true,"hoverEvent":{"action":"show_text","value":{"text":"","extra":[{"text":"test/tmp/backups/2021-01-01_00-00-00.tar.gz"}]}}}]
 save-off
+save-all
+save-all flush
 save-on
 save-all
 tellraw @a ["",{"text":"[Backup] ","color":"gray","italic":true},{"text":"Backup complete!","color":"green","italic":true,"hoverEvent":{"action":"show_text","value":{"text":"","extra":[{"text":"0 s, 4.0K/4.0K, 316%"}]}}}]
diff --git a/test/data/test-chat-prefix.txt b/test/data/test-chat-prefix.txt
index 33d6856..4b512e6 100644
--- a/test/data/test-chat-prefix.txt
+++ b/test/data/test-chat-prefix.txt
@@ -1,5 +1,7 @@
 tellraw @a ["",{"text":"[Hello] ","color":"gray","italic":true},{"text":"Starting backup...","color":"gray","italic":true,"hoverEvent":{"action":"show_text","value":{"text":"","extra":[{"text":"test/tmp/backups/2021-01-01_00-00-00.tar.gz"}]}}}]
 save-off
+save-all
+save-all flush
 save-on
 save-all
 tellraw @a ["",{"text":"[Hello] ","color":"gray","italic":true},{"text":"Hello complete!","color":"green","italic":true,"hoverEvent":{"action":"show_text","value":{"text":"","extra":[{"text":"0 s, 4.0K/4.0K, 316%"}]}}}]
diff --git a/test/test.sh b/test/test.sh
index 42a2991..7083909 100755
--- a/test/test.sh
+++ b/test/test.sh
@@ -346,7 +346,7 @@ test-nonzero-exit-warning () {
 test-screen-interface () {
   TIMESTAMP="$(date +%F_%H-%M-%S --date="2021-01-01")"
   ./backup.sh -i "$TEST_TMP/server/world" -o "$TEST_TMP/backups" -s "$SCREEN_TMP" -f "$TIMESTAMP"
-  EXPECTED_CONTENTS=$(echo -e "save-off\nsave-on\nsave-all") 
+  EXPECTED_CONTENTS=$(echo -e "save-off\nsave-all\nsave-all flush\nsave-on\nsave-all") 
   SCREEN_CONTENTS="$(cat "$TEST_TMP/screen-output")"
   assertEquals "$EXPECTED_CONTENTS" "$SCREEN_CONTENTS" 
 }
@@ -354,7 +354,7 @@ test-screen-interface () {
 test-tmux-interface () {
   TIMESTAMP="$(date +%F_%H-%M-%S --date="2021-01-01")"
   ./backup.sh -w tmux -i "$TEST_TMP/server/world" -o "$TEST_TMP/backups" -s "$SCREEN_TMP" -f "$TIMESTAMP"
-  EXPECTED_CONTENTS=$(echo -e "save-off\nsave-on\nsave-all") 
+  EXPECTED_CONTENTS=$(echo -e "save-off\nsave-all\nsave-all flush\nsave-on\nsave-all") 
   SCREEN_CONTENTS="$(cat "$TEST_TMP/tmux-output")"
   assertEquals "$EXPECTED_CONTENTS" "$SCREEN_CONTENTS" 
 }
@@ -362,8 +362,8 @@ test-tmux-interface () {
 test-rcon-interface () {
   TIMESTAMP="$(date +%F_%H-%M-%S --date="2021-01-01")"
   ./backup.sh -w rcon -i "$TEST_TMP/server/world" -o "$TEST_TMP/backups" -s "localhost:$RCON_PORT:$RCON_PASSWORD" -f "$TIMESTAMP"
-  EXPECTED_CONTENTS=$(echo -e "save-off\nsave-on\nsave-all") 
-  SCREEN_CONTENTS="$(head -n3 "$TEST_TMP/rcon-output")"
+  EXPECTED_CONTENTS=$(echo -e "save-off\nsave-all\nsave-all flush\nsave-on\nsave-all") 
+  SCREEN_CONTENTS="$(head -n5 "$TEST_TMP/rcon-output")"
   assertEquals "$EXPECTED_CONTENTS" "$SCREEN_CONTENTS" 
 }