diff --git a/client/js/controllers/post_upload_controller.js b/client/js/controllers/post_upload_controller.js
index 2ad02afc..4c4ec68f 100644
--- a/client/js/controllers/post_upload_controller.js
+++ b/client/js/controllers/post_upload_controller.js
@@ -175,9 +175,11 @@ class PostUploadController {
         // if uploadable.source is ever going to be a valid field (e.g when setting source directly in the upload window)
         // you'll need to change the line below to `post.source = uploadable.source || uploadable.url;`
         if (uploadable.url) {
+            // For now, if the input is a URL, flmt will be same as creation date
             post.source = uploadable.url;
+        } else {
+            post.fileLastModifiedTime = uploadable.file.lastModified;
         }
-        post.fileLastModifiedTime = uploadable.file.lastModified; // The client already reads the data anyway, which is convenient
         return post;
     }
 }
diff --git a/server/szurubooru/api/post_api.py b/server/szurubooru/api/post_api.py
index 9262af56..86c2908c 100644
--- a/server/szurubooru/api/post_api.py
+++ b/server/szurubooru/api/post_api.py
@@ -89,7 +89,7 @@ def create_post(
     posts.update_post_flags(post, flags)
     if ctx.has_param("fileLastModifiedTime"):
         posts.update_post_file_last_modified_time(
-            post, ctx.get_as_param("file_last_modified_time")
+            post, ctx.get_param_as_int("fileLastModifiedTime")
         )
     if ctx.has_file("thumbnail"):
         posts.update_post_thumbnail(post, ctx.get_file("thumbnail"))