diff --git a/README.md b/README.md
index 7b38ad191..19bf193a6 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ If you like **Sonoff-Tasmota**, give it a star, or fork it and contribute!
 ### Development:
 [![Build Status](https://img.shields.io/travis/arendst/Sonoff-Tasmota.svg)](https://travis-ci.org/arendst/Sonoff-Tasmota)
 
-Current version is **5.13.0** - See [sonoff/_releasenotes.ino](https://github.com/arendst/Sonoff-Tasmota/blob/development/sonoff/_releasenotes.ino) for change information.
+Current version is **5.13.0a** - See [sonoff/_releasenotes.ino](https://github.com/arendst/Sonoff-Tasmota/blob/development/sonoff/_releasenotes.ino) for change information.
 
 ### Quick install
 Download one of the released binaries from https://github.com/arendst/Sonoff-Tasmota/releases and flash it to your hardware as documented in the wiki.
diff --git a/sonoff/_releasenotes.ino b/sonoff/_releasenotes.ino
index d08e1bb39..3bb2238c9 100644
--- a/sonoff/_releasenotes.ino
+++ b/sonoff/_releasenotes.ino
@@ -1,4 +1,7 @@
-/* 5.13.0 20180430
+/* 5.13.0a
+ * Fix JSON buffers size too small for execution in some situations (#2580)
+ *
+ * 5.13.0 20180430
  * Change platformio option sonoff-ds18x20 to sonoff-allsensors enabling ds18x20 and all other sensors in one image
  * Change status display of Ssid and SetOption
  * Change default option SetOption15 from 0 to 1 providing better initial PWM experience
diff --git a/sonoff/sonoff.ino b/sonoff/sonoff.ino
index a3f7b2866..554a4858e 100644
--- a/sonoff/sonoff.ino
+++ b/sonoff/sonoff.ino
@@ -25,7 +25,7 @@
     - Select IDE Tools - Flash Size: "1M (no SPIFFS)"
   ====================================================*/
 
-#define VERSION                0x050D0000   // 5.13.0
+#define VERSION                0x050D0001   // 5.13.0a
 
 // Location specific includes
 #include <core_version.h>                   // Arduino_Esp8266 version information (ARDUINO_ESP8266_RELEASE and ARDUINO_ESP8266_RELEASE_2_3_0)
diff --git a/sonoff/xdrv_09_timers.ino b/sonoff/xdrv_09_timers.ino
index aa1287f20..e85349da7 100644
--- a/sonoff/xdrv_09_timers.ino
+++ b/sonoff/xdrv_09_timers.ino
@@ -354,7 +354,7 @@ boolean TimerCommand()
 #ifndef USE_RULES
         if (devices_present) {
 #endif
-          StaticJsonBuffer<200> jsonBuffer;
+          StaticJsonBuffer<256> jsonBuffer;
           JsonObject& root = jsonBuffer.parseObject(dataBufUc);
           if (!root.success()) {
             snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("{\"" D_CMND_TIMER "%d\":\"" D_JSON_INVALID_JSON "\"}"), index); // JSON decode failed
diff --git a/sonoff/xdrv_10_rules.ino b/sonoff/xdrv_10_rules.ino
index f92edcf55..b07bea5b7 100644
--- a/sonoff/xdrv_10_rules.ino
+++ b/sonoff/xdrv_10_rules.ino
@@ -181,7 +181,7 @@ bool RulesRuleMatch(String &event, String &rule)
   }
 
   // Step2: Search rule_task and rule_name
-  StaticJsonBuffer<400> jsonBuf;
+  StaticJsonBuffer<1024> jsonBuf;
   JsonObject &root = jsonBuf.parseObject(event);
   if (!root.success()) { return false; }               // No valid JSON data