diff --git a/include/swupd.h b/include/swupd.h
index b056f8ba..2a9c30bd 100644
--- a/include/swupd.h
+++ b/include/swupd.h
@@ -7,8 +7,8 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
-#include <sys/queue.h>
 #include <string.h>
+#include <sys/queue.h>
 
 #include "list.h"
 #include "swupd-error.h"
@@ -80,6 +80,7 @@ struct version_container {
 
 struct header;
 
+extern bool allow_mix_collisions;
 extern bool verbose_time;
 extern bool force;
 extern bool migrate;
diff --git a/src/globals.c b/src/globals.c
index 19b11c9a..f637630a 100644
--- a/src/globals.c
+++ b/src/globals.c
@@ -30,7 +30,7 @@
 
 #include "config.h"
 #include "swupd.h"
-
+bool allow_mix_collisions = false;
 bool force = false;
 bool migrate = false;
 bool sigcheck = true;
diff --git a/src/main.c b/src/main.c
index 721b8e39..b8293d4a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -54,6 +54,7 @@ static const struct option prog_opts[] = {
 	{ "no-scripts", no_argument, 0, 'N' },
 	{ "no-boot-update", no_argument, 0, 'b' },
 	{ "migrate", no_argument, 0, 'b' },
+	{ "allow-mix-collisions", no_argument, 0, 'a' },
 	{ 0, 0, 0, 0 }
 };
 
@@ -91,12 +92,15 @@ static bool parse_options(int argc, char **argv)
 {
 	int opt;
 
-	while ((opt = getopt_long(argc, argv, "hxnIdtNbmu:P:c:v:sF:p:S:C:", prog_opts, NULL)) != -1) {
+	while ((opt = getopt_long(argc, argv, "hxnIdtNbmau:P:c:v:sF:p:S:C:", prog_opts, NULL)) != -1) {
 		switch (opt) {
 		case '?':
 		case 'h':
 			print_help(argv[0]);
 			exit(EXIT_SUCCESS);
+		case 'a':
+			allow_mix_collisions = true;
+			break;
 		case 'd':
 			download_only = true;
 			break;
diff --git a/src/manifest.c b/src/manifest.c
index a4594542..23f193ee 100644
--- a/src/manifest.c
+++ b/src/manifest.c
@@ -1546,5 +1546,5 @@ int enforce_compliant_manifest(struct file **a, struct file **b, int searchsize,
 			ret++;
 		}
 	}
-	return ret; // No collisions were found, so manifest is purely additive
+	return ret; // If collisions were found, so manifest is purely additive
 }
diff --git a/src/update.c b/src/update.c
index 2a69389d..04e188a2 100644
--- a/src/update.c
+++ b/src/update.c
@@ -368,6 +368,10 @@ version_check:
 			ret = check_manifests_uniqueness(server_version, mix_server_version);
 			if (ret) {
 				printf("\n\t!! %i collisions were found between mix and upstream, please re-create mix !!\n", ret);
+				if (!allow_mix_collisions) {
+					ret = EXIT_FAILURE;
+					goto clean_curl;
+				}
 			}
 
 			/* Update the clearversion that will be used to generate the new mix content */