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docs/user-guide/check-alive.md

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+# Check Alive
+
+**Check Alive** is the plugin's "are you still around?" mechanism. It is available in **advanced mode**.
+
+![Advanced mode toggle](../img/settings-advanced-mode.png){ .screenshot }
+*Advanced mode exposes Check Alive and the other fine-grained parameters.*
+
+## What it does
+
+Check Alive defines a period of inactivity. When you open Electrum and more than that period has passed since the last postponement, the plugin asks whether you want to **push your delivery date further out** — because you are evidently still alive.
+
+![Check Alive parameter](../img/settings-check-alive.png){ .screenshot }
+*The threshold can be expressed as a relative period or an absolute date.*
+
+## Example
+
+You set a delivery date **2 years** out, with Check Alive at **6 months**.
+
+| What you do | What happens |
+|---|---|
+| You open Electrum after 3 months | Nothing — you are inside the Check Alive window |
+| You open Electrum after 7 months | The plugin points out that your delivery date is now only 1 year and 5 months away, and offers to postpone it |
+| You stop opening Electrum altogether | Nothing postpones the will. On the delivery date, the Will-Executors broadcast it |
+
+As long as you keep using Electrum within the Check Alive window and accept the prompts, your will is never executed.
+
+!!! tip "Disabling it for a quick test"
+    Setting Check Alive to a **date in the past** effectively switches it off. This is what you want when testing the plugin with a delivery time only a few hours away, so the prompt doesn't get in the way.
+
+!!! warning "Postponing is not free"
+    Accepting a postponement may require invalidating the previously committed transaction on-chain, which costs a miner fee. See [Postponing vs anticipating](updating.md#postponing-vs-anticipating).