diff --git a/src/main/java/com/crowdin/cli/commands/actions/UploadSourcesAction.java b/src/main/java/com/crowdin/cli/commands/actions/UploadSourcesAction.java
index 3d202005f..b298d3fdd 100644
--- a/src/main/java/com/crowdin/cli/commands/actions/UploadSourcesAction.java
+++ b/src/main/java/com/crowdin/cli/commands/actions/UploadSourcesAction.java
@@ -338,7 +338,11 @@ public void act(Outputter out, PropertiesWithFiles pb, ProjectClient client) {
 
                     })
                     .collect(Collectors.toList());
-                ConcurrencyUtil.executeAndWait(taskss, debug);
+                if (isStringsBasedProject) {
+                    ConcurrencyUtil.executeAndWaitSingleThread(taskss, debug);
+                } else {
+                    ConcurrencyUtil.executeAndWait(taskss, debug);
+                }
             })
             .collect(Collectors.toList());
         ConcurrencyUtil.executeAndWaitSingleThread(tasks, debug);
diff --git a/src/main/java/com/crowdin/cli/commands/actions/UploadTranslationsAction.java b/src/main/java/com/crowdin/cli/commands/actions/UploadTranslationsAction.java
index 1178f0caa..64d5807c7 100644
--- a/src/main/java/com/crowdin/cli/commands/actions/UploadTranslationsAction.java
+++ b/src/main/java/com/crowdin/cli/commands/actions/UploadTranslationsAction.java
@@ -226,7 +226,11 @@ public void act(Outputter out, PropertiesWithFiles pb, ProjectClient client) {
                     })
                     .collect(Collectors.toList());
             }
-            ConcurrencyUtil.executeAndWait(tasks, debug);
+            if (isStringsBasedProject) {
+                ConcurrencyUtil.executeAndWaitSingleThread(tasks, debug);
+            } else {
+                ConcurrencyUtil.executeAndWait(tasks, debug);
+            }
 
             if (containsErrors.get()) {
                 throw new RuntimeException(RESOURCE_BUNDLE.getString("error.execution_contains_errors"));
diff --git a/src/main/java/com/crowdin/cli/utils/concurrency/ConcurrencyUtil.java b/src/main/java/com/crowdin/cli/utils/concurrency/ConcurrencyUtil.java
index 4250115e0..011f5dd05 100644
--- a/src/main/java/com/crowdin/cli/utils/concurrency/ConcurrencyUtil.java
+++ b/src/main/java/com/crowdin/cli/utils/concurrency/ConcurrencyUtil.java
@@ -20,7 +20,6 @@ private ConcurrencyUtil() {
      */
     public static void executeAndWait(List<Runnable> tasks, boolean debug) {
         run(tasks, CROWDIN_API_MAX_CONCURRENT_REQUESTS, tasks.size() * 2, debug);
-
     }
 
     public static void executeAndWaitSingleThread(List<Runnable> tasks, boolean debug) {
@@ -28,7 +27,7 @@ public static void executeAndWaitSingleThread(List<Runnable> tasks, boolean debu
     }
 
     private static void run(List<Runnable> tasks, int threadQnt, int minutesWait, boolean debug) {
-        if (Objects.isNull(tasks) || tasks.size() == 0) {
+        if (Objects.isNull(tasks) || tasks.isEmpty()) {
             return;
         }
         ExecutorService executor = CrowdinExecutorService.newFixedThreadPool(threadQnt, debug);