diff --git a/src/grib_filepool.c b/src/grib_filepool.c
index d9bbe5101..4dc681354 100644
--- a/src/grib_filepool.c
+++ b/src/grib_filepool.c
@@ -255,6 +255,7 @@ grib_file* grib_file_open(const char* filename, const char* mode, int* err)
             GRIB_MUTEX_UNLOCK(&mutex1);
             return NULL;
         }
+        if (file->mode) free(file->mode);
         file->mode = strdup(mode);
         if (file_pool.context->io_buffer_size) {
 #ifdef POSIX_MEMALIGN
diff --git a/tools/grib_tools.c b/tools/grib_tools.c
index 385709282..cb74e1774 100644
--- a/tools/grib_tools.c
+++ b/tools/grib_tools.c
@@ -150,6 +150,14 @@ int grib_tool(int argc, char** argv)
     grib_context* c        = grib_context_get_default();
     global_options.context = c;
 
+    /* This is a consequence of ECC-440.
+     * We want to keep the output file(s) opened as various
+     * messages are appended to them. Otherwise they will be opened/closed
+     * multiple times.
+     */
+    if (c->file_pool_max_opened_files == 0)
+        c->file_pool_max_opened_files = 200;
+
 #ifdef ENABLE_FLOATING_POINT_EXCEPTIONS
     feenableexcept(FE_ALL_EXCEPT & ~FE_INEXACT);
 #endif