diff --git a/esphome/esp-attobattery.yaml b/esphome/esp-attobattery.yaml
index 6576b0e..fc8458d 100644
--- a/esphome/esp-attobattery.yaml
+++ b/esphome/esp-attobattery.yaml
@@ -23,7 +23,7 @@ substitutions:
 
   # Project Naming
   project_name: "Generic ESP8266.D1 Mini" # Project Details
-  project_version: "v1.1" # Project V denotes release of yaml file, allowing checking of deployed vs latest version
+project_version: "v1.2" # Standardized MQTT payloads: "ON"/"OFF" → "On"/"Off"
 
   # Passwords & Secrets
   api_key: !secret esp-api_key # unfortunately you can't use substitutions inside secrets names