diff --git a/GITHUB_SHA.h b/GITHUB_SHA.h
index f1dae0d..5101747 100644
--- a/GITHUB_SHA.h
+++ b/GITHUB_SHA.h
@@ -1 +1 @@
-#define GITHUB_SHA "devel-202409300806Z"
+#define GITHUB_SHA "devel-heartbeat202410192325ZZ"
diff --git a/version.h b/version.h
index e6d43d3..52e3be5 100644
--- a/version.h
+++ b/version.h
@@ -3,7 +3,8 @@
 
 #include "StringFormatter.h"
 
-#define VERSION "5.2.85"
+#define VERSION "5.2.86"
+// 5.2.86 - add HEARTBEAT_CRITICAL to enforce heartbeat check
 // 5.2.85 - IO_TM1638 driver, SEG7 Exrail macro and _s7 segment pattern generator.
 // 5.2.84 - Fix TrackManager setDCCSignal and setPROGSignal for STM32 shadowing of PORTG/PORTH - this time it really is correct!
 // 5.2.83 - Various STM32 related fixes for serial ports, I2C pullups now turned off, and shadowing of PORTG/PORTH for TrackManager now correct